refactor: make session join leave platform-neutral

Convert join/leave interaction commands to PlatformUser, PlatformGroup, and PlatformMessageRef. Persist and look up participants by platform identity while keeping Telegram callbacks intact. Add V017 migration and TDD coverage. Bump version to 2.1.1.

.gitea/workflows/deploy.yml

@@ -6,7 +6,7 @@ on:
       - main 
 
 env:
-  VERSION: 2.0.0
+  VERSION: 2.1.1
 
 jobs:
   # ЧАСТЬ 1: Собираем образы и кладем в Gitea (чтобы делиться с ребятами)

Directory.Build.props

@@ -1,6 +1,6 @@
 <Project>
   <PropertyGroup>
-    <Version>2.0.0</Version>
+    <Version>2.1.1</Version>
     <TargetFramework>net10.0</TargetFramework>
     <LangVersion>preview</LangVersion>
     <Nullable>enable</Nullable>

README.md

@@ -4,7 +4,7 @@
 
 Проект разработан с упором на производительность, архитектуру Vertical Slice, Native AOT (для бота) и удобство развертывания с использованием .NET Aspire.
 
-**Текущая версия:** `v1.15.0`.
+**Текущая версия:** `v2.0.1`.
 
 ---
 

compose.yaml

@@ -49,7 +49,7 @@ services:
         crond -f
 
   bot:
-    image: git.codeanddice.ru/toutsu/gmrelay-bot:2.0.0
+    image: git.codeanddice.ru/toutsu/gmrelay-bot:2.1.1
     restart: always
     depends_on:
       db:
@@ -67,7 +67,7 @@ services:
       retries: 3
 
   web:
-    image: git.codeanddice.ru/toutsu/gmrelay-web:2.0.0
+    image: git.codeanddice.ru/toutsu/gmrelay-web:2.1.1
     restart: always
     depends_on:
       db:

docs/superpowers/plans/2026-05-15-platform-messenger-contracts.md

@@ -0,0 +1,560 @@
+# Platform Messenger Contracts Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Implement issue #24 by adding platform-neutral platform identity and messaging contracts, then routing the Telegram session flows through a Telegram adapter without changing Telegram behavior.
+
+**Architecture:** Keep update routing and Telegram update parsing at the `GmRelay.Bot.Infrastructure.Telegram` boundary, but move outbound messaging decisions behind `GmRelay.Shared.Platform.IPlatformMessenger`. `GmRelay.Shared` owns platform-neutral DTOs and contracts; `GmRelay.Bot` owns `TelegramPlatformMessenger`, which translates neutral requests into `Telegram.Bot` calls and reuses the existing Telegram renderers/editing rules.
+
+**Tech Stack:** .NET 10, C# preview, xUnit, Dapper.AOT constraints, Telegram.Bot in `GmRelay.Bot` only, platform-neutral shared contracts in `GmRelay.Shared`.
+
+---
+
+## Issue Context
+
+- Gitea issue: #24, `refactor: ввести PlatformKind, PlatformUser, PlatformGroup и IPlatformMessenger`
+- Labels: `area:bot`, `area:platform`, `area:shared`, `platform:multi`, `type:refactor`, `pending-approval`
+- Acceptance criteria:
+  - New contracts live in a platform-neutral layer.
+  - Telegram flow goes through the adapter without behavior changes.
+  - A future DiscordBot can reference the contract without depending on Telegram assemblies.
+
+## Proposed Version Bump
+
+Current version is `2.0.0` in:
+
+- `Directory.Build.props`
+- `compose.yaml`
+- `.gitea/workflows/deploy.yml`
+- `src/GmRelay.Web/Components/Layout/NavMenu.razor`
+
+Issue label is `type:refactor`; per workflow rules this is not a major bump and has no user-facing feature label. Proposed bump: `2.0.0` -> `2.0.1`.
+
+## Files
+
+- Create: `src/GmRelay.Shared/Platform/PlatformKind.cs`
+- Create: `src/GmRelay.Shared/Platform/PlatformUser.cs`
+- Create: `src/GmRelay.Shared/Platform/PlatformGroup.cs`
+- Create: `src/GmRelay.Shared/Platform/PlatformMessageContracts.cs`
+- Create: `src/GmRelay.Shared/Platform/IPlatformMessenger.cs`
+- Create: `src/GmRelay.Bot/Infrastructure/Telegram/TelegramPlatformMessenger.cs`
+- Create: `tests/GmRelay.Bot.Tests/Platform/PlatformContractsTests.cs`
+- Create: `tests/GmRelay.Bot.Tests/Infrastructure/Telegram/TelegramPlatformMessengerSourceTests.cs`
+- Modify: `src/GmRelay.Bot/Program.cs`
+- Modify: `src/GmRelay.Bot/Features/Notifications/DirectSessionNotificationSender.cs`
+- Modify: `src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs`
+- Modify: `src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs`
+- Modify: `src/GmRelay.Bot/Features/Sessions/CreateSession/CancelSessionHandler.cs`
+- Modify: `src/GmRelay.Bot/Features/Sessions/CreateSession/PromoteWaitlistedPlayerHandler.cs`
+- Modify: `src/GmRelay.Bot/Features/Sessions/RescheduleSession/InitiateRescheduleHandler.cs`
+- Modify: `src/GmRelay.Bot/Features/Sessions/RescheduleSession/HandleRescheduleTimeInputHandler.cs`
+- Modify: `src/GmRelay.Bot/Features/Sessions/RescheduleSession/HandleRescheduleVoteHandler.cs`
+- Modify: `src/GmRelay.Bot/Features/Sessions/RescheduleSession/RescheduleVotingDeadlineService.cs`
+- Modify: `src/GmRelay.Bot/Features/Sessions/ExportCalendar/ExportCalendarHandler.cs`
+- Modify: version files listed above
+
+## Design
+
+### Shared Contracts
+
+`PlatformKind` is a sentinel enum where `Max` is not a sendable platform:
+
+```csharp
+namespace GmRelay.Shared.Platform;
+
+public enum PlatformKind
+{
+    Telegram = 0,
+    Discord = 1,
+    Max = 2
+}
+```
+
+`PlatformUser` and `PlatformGroup` carry external platform identity while keeping current Telegram IDs representable as strings:
+
+```csharp
+namespace GmRelay.Shared.Platform;
+
+public sealed record PlatformUser(
+    PlatformKind Platform,
+    string ExternalUserId,
+    string DisplayName,
+    string? ExternalUsername);
+
+public sealed record PlatformGroup(
+    PlatformKind Platform,
+    string ExternalGroupId,
+    string DisplayName,
+    string? ExternalChannelId = null,
+    string? ExternalThreadId = null);
+```
+
+Outbound message contracts stay independent of Telegram/Discord SDK types:
+
+```csharp
+using GmRelay.Shared.Rendering;
+
+namespace GmRelay.Shared.Platform;
+
+public sealed record PlatformMessageRef(
+    PlatformKind Platform,
+    string ExternalGroupId,
+    string? ExternalThreadId,
+    string ExternalMessageId);
+
+public sealed record PlatformMessageAction(
+    string Key,
+    string Label,
+    string Payload);
+
+public sealed record PlatformScheduleMessage(
+    PlatformGroup Group,
+    SessionBatchViewModel View,
+    PlatformMessageRef? ExistingMessage,
+    string? ImageReference = null);
+
+public sealed record PlatformPrivateMessage(
+    PlatformUser Recipient,
+    string HtmlText);
+
+public sealed record PlatformInteractionReply(
+    string InteractionId,
+    string Text,
+    bool ShowAlert = false);
+
+public sealed record PlatformCalendarFile(
+    PlatformGroup Group,
+    string FileName,
+    byte[] Content,
+    string CaptionHtml,
+    IReadOnlyList<PlatformMessageAction> Actions);
+```
+
+`IPlatformMessenger` exposes the required outward operations:
+
+```csharp
+namespace GmRelay.Shared.Platform;
+
+public interface IPlatformMessenger
+{
+    Task<PlatformMessageRef> SendScheduleAsync(PlatformScheduleMessage message, CancellationToken ct);
+    Task UpdateScheduleAsync(PlatformScheduleMessage message, CancellationToken ct);
+    Task SendGroupMessageAsync(PlatformGroup group, string htmlText, CancellationToken ct);
+    Task SendPrivateMessageAsync(PlatformPrivateMessage message, CancellationToken ct);
+    Task AnswerInteractionAsync(PlatformInteractionReply reply, CancellationToken ct);
+    Task SendCalendarFileAsync(PlatformCalendarFile file, CancellationToken ct);
+}
+```
+
+### Telegram Adapter
+
+`TelegramPlatformMessenger` lives in `GmRelay.Bot.Infrastructure.Telegram`, depends on `ITelegramBotClient`, and translates neutral DTOs to existing Telegram calls:
+
+- `SendScheduleAsync` renders `SessionBatchViewModel` with `TelegramSessionBatchRenderer.Render`.
+- `UpdateScheduleAsync` calls `BatchMessageEditor.EditBatchMessageAsync`.
+- `SendGroupMessageAsync` calls `SendMessage` with `ParseMode.Html` and optional `messageThreadId`.
+- `SendPrivateMessageAsync` calls `SendMessage` to `PlatformUser.ExternalUserId`.
+- `AnswerInteractionAsync` calls `AnswerCallbackQuery`.
+- `SendCalendarFileAsync` calls `SendDocument` and maps URL actions to inline keyboard buttons.
+
+### Handler Scope
+
+Refactor outbound Telegram calls in these flows to `IPlatformMessenger`:
+
+- Join/leave/promote waitlist schedule updates and callback replies.
+- Cancel schedule update, group cancellation message, direct notification and callback reply.
+- Reschedule initiation, voting message updates, immediate reschedule schedule update, direct notifications and callback replies.
+- Export calendar file sending.
+
+Keep Telegram inbound DTOs at the boundary for now:
+
+- `UpdateRouter` still receives `Telegram.Bot.Types.Update`.
+- Text message parsing in reschedule input still receives `Telegram.Bot.Types.Message`.
+- `CreateSessionHandler` can keep photo/topic creation via `ITelegramBotClient` because issue #24 targets outbound schedule/interaction/private/calendar contract, not replacing all Telegram update primitives in one PR.
+
+## Tasks
+
+### Task 1: RED - Shared Contract Tests
+
+**Files:**
+- Create: `tests/GmRelay.Bot.Tests/Platform/PlatformContractsTests.cs`
+
+- [ ] **Step 1: Write failing tests for neutral contracts**
+
+```csharp
+using GmRelay.Shared.Platform;
+using GmRelay.Shared.Rendering;
+
+namespace GmRelay.Bot.Tests.Platform;
+
+public sealed class PlatformContractsTests
+{
+    [Fact]
+    public void PlatformKind_ShouldDefineTelegramDiscordAndMaxSentinel()
+    {
+        Assert.Equal(0, (int)PlatformKind.Telegram);
+        Assert.Equal(1, (int)PlatformKind.Discord);
+        Assert.Equal(2, (int)PlatformKind.Max);
+    }
+
+    [Fact]
+    public void PlatformContracts_ShouldBeTelegramAssemblyFree()
+    {
+        var contractTypes = new[]
+        {
+            typeof(PlatformUser),
+            typeof(PlatformGroup),
+            typeof(PlatformMessageRef),
+            typeof(PlatformMessageAction),
+            typeof(PlatformScheduleMessage),
+            typeof(PlatformPrivateMessage),
+            typeof(PlatformInteractionReply),
+            typeof(PlatformCalendarFile),
+            typeof(IPlatformMessenger)
+        };
+
+        Assert.All(contractTypes, type =>
+            Assert.DoesNotContain(
+                "Telegram",
+                string.Join(" ", type.Assembly.GetReferencedAssemblies().Select(value => value.Name)),
+                StringComparison.OrdinalIgnoreCase));
+    }
+
+    [Fact]
+    public void PlatformScheduleMessage_ShouldCarrySharedViewModelWithoutPlatformTypes()
+    {
+        var sessionId = Guid.Parse("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa");
+        var view = SessionBatchViewBuilder.Build(
+            "Campaign",
+            [new SessionBatchDto(sessionId, new DateTime(2026, 5, 15, 16, 0, 0, DateTimeKind.Utc), "Planned", 4, "https://example.test/game")],
+            []);
+        var group = new PlatformGroup(PlatformKind.Discord, "guild-1", "Guild", "channel-1", "thread-1");
+
+        var message = new PlatformScheduleMessage(group, view, ExistingMessage: null);
+
+        Assert.Equal(PlatformKind.Discord, message.Group.Platform);
+        Assert.Same(view, message.View);
+    }
+}
+```
+
+- [ ] **Step 2: Run tests and verify RED**
+
+Run:
+
+```powershell
+dotnet test tests/GmRelay.Bot.Tests/GmRelay.Bot.Tests.csproj --filter PlatformContractsTests
+```
+
+Expected: compile failure because `GmRelay.Shared.Platform` types do not exist.
+
+### Task 2: GREEN - Add Shared Contracts
+
+**Files:**
+- Create: `src/GmRelay.Shared/Platform/PlatformKind.cs`
+- Create: `src/GmRelay.Shared/Platform/PlatformUser.cs`
+- Create: `src/GmRelay.Shared/Platform/PlatformGroup.cs`
+- Create: `src/GmRelay.Shared/Platform/PlatformMessageContracts.cs`
+- Create: `src/GmRelay.Shared/Platform/IPlatformMessenger.cs`
+
+- [ ] **Step 1: Add the contract files exactly as described in the Design section**
+- [ ] **Step 2: Run PlatformContractsTests and verify GREEN**
+
+Run:
+
+```powershell
+dotnet test tests/GmRelay.Bot.Tests/GmRelay.Bot.Tests.csproj --filter PlatformContractsTests
+```
+
+Expected: `Passed`.
+
+### Task 3: RED - Adapter and Flow Source Tests
+
+**Files:**
+- Create: `tests/GmRelay.Bot.Tests/Infrastructure/Telegram/TelegramPlatformMessengerSourceTests.cs`
+
+- [ ] **Step 1: Write source tests for adapter wiring and target flows**
+
+```csharp
+namespace GmRelay.Bot.Tests.Infrastructure.Telegram;
+
+public sealed class TelegramPlatformMessengerSourceTests
+{
+    [Fact]
+    public async Task Program_ShouldRegisterTelegramPlatformMessenger()
+    {
+        var program = await ReadRepositoryFileAsync("src/GmRelay.Bot/Program.cs");
+
+        Assert.Contains("IPlatformMessenger", program, StringComparison.Ordinal);
+        Assert.Contains("TelegramPlatformMessenger", program, StringComparison.Ordinal);
+    }
+
+    [Theory]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/CreateSession/CancelSessionHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/CreateSession/PromoteWaitlistedPlayerHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/RescheduleSession/InitiateRescheduleHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/RescheduleSession/HandleRescheduleTimeInputHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/RescheduleSession/HandleRescheduleVoteHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/RescheduleSession/RescheduleVotingDeadlineService.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/ExportCalendar/ExportCalendarHandler.cs")]
+    public async Task SessionFlows_ShouldUsePlatformMessengerForOutboundTelegramWork(string relativePath)
+    {
+        var source = await ReadRepositoryFileAsync(relativePath);
+
+        Assert.Contains("IPlatformMessenger", source, StringComparison.Ordinal);
+        Assert.DoesNotContain("BatchMessageEditor.EditBatchMessageAsync", source, StringComparison.Ordinal);
+        Assert.DoesNotContain(".AnswerCallbackQuery(", source, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public async Task TelegramPlatformMessenger_ShouldOwnTelegramBotClientCalls()
+    {
+        var source = await ReadRepositoryFileAsync("src/GmRelay.Bot/Infrastructure/Telegram/TelegramPlatformMessenger.cs");
+
+        Assert.Contains("ITelegramBotClient", source, StringComparison.Ordinal);
+        Assert.Contains("BatchMessageEditor.EditBatchMessageAsync", source, StringComparison.Ordinal);
+        Assert.Contains("AnswerCallbackQuery", source, StringComparison.Ordinal);
+        Assert.Contains("SendDocument", source, StringComparison.Ordinal);
+    }
+
+    private static async Task<string> ReadRepositoryFileAsync(string relativePath)
+    {
+        var directory = new DirectoryInfo(AppContext.BaseDirectory);
+        while (directory is not null)
+        {
+            var candidate = Path.Combine(directory.FullName, relativePath);
+            if (File.Exists(candidate))
+            {
+                return await File.ReadAllTextAsync(candidate);
+            }
+
+            directory = directory.Parent;
+        }
+
+        throw new FileNotFoundException($"Could not locate repository file '{relativePath}'.");
+    }
+}
+```
+
+- [ ] **Step 2: Run tests and verify RED**
+
+Run:
+
+```powershell
+dotnet test tests/GmRelay.Bot.Tests/GmRelay.Bot.Tests.csproj --filter TelegramPlatformMessengerSourceTests
+```
+
+Expected: failures because `TelegramPlatformMessenger` is missing and handlers still call Telegram APIs directly.
+
+### Task 4: GREEN - Implement TelegramPlatformMessenger and Registration
+
+**Files:**
+- Create: `src/GmRelay.Bot/Infrastructure/Telegram/TelegramPlatformMessenger.cs`
+- Modify: `src/GmRelay.Bot/Program.cs`
+
+- [ ] **Step 1: Implement adapter**
+
+Implementation notes:
+
+- Parse Telegram chat/thread/message IDs from neutral string IDs with `long.Parse` and `int.Parse`.
+- Use `ParseMode.Html` for HTML text.
+- Map `PlatformMessageAction` URLs to `InlineKeyboardButton.WithUrl`.
+- Return a `PlatformMessageRef` with message IDs converted to strings.
+
+- [ ] **Step 2: Register adapter**
+
+Add `using GmRelay.Shared.Platform;` and register:
+
+```csharp
+builder.Services.AddSingleton<IPlatformMessenger, TelegramPlatformMessenger>();
+```
+
+- [ ] **Step 3: Run adapter source tests**
+
+Run:
+
+```powershell
+dotnet test tests/GmRelay.Bot.Tests/GmRelay.Bot.Tests.csproj --filter TelegramPlatformMessengerSourceTests
+```
+
+Expected: some handler source tests still fail until Task 5.
+
+### Task 5: GREEN - Refactor Session Flows Through Adapter
+
+**Files:**
+- Modify target handler files listed in Task 3
+- Modify: `src/GmRelay.Bot/Features/Notifications/DirectSessionNotificationSender.cs`
+
+- [ ] **Step 1: Replace constructor dependencies**
+
+Use `IPlatformMessenger messenger` in target handlers for outbound operations. Keep `ITelegramBotClient` only where the handler still performs inbound Telegram-specific work that is out of scope, such as message deletion or forum topic creation.
+
+- [ ] **Step 2: Convert Telegram IDs to neutral platform objects**
+
+Use helper code equivalent to:
+
+```csharp
+private static PlatformGroup TelegramGroup(long chatId, string? title, int? threadId = null)
+    => new(
+        PlatformKind.Telegram,
+        chatId.ToString(System.Globalization.CultureInfo.InvariantCulture),
+        title ?? "Telegram chat",
+        ExternalChannelId: chatId.ToString(System.Globalization.CultureInfo.InvariantCulture),
+        ExternalThreadId: threadId?.ToString(System.Globalization.CultureInfo.InvariantCulture));
+
+private static PlatformUser TelegramUser(long telegramId, string displayName, string? username = null)
+    => new(
+        PlatformKind.Telegram,
+        telegramId.ToString(System.Globalization.CultureInfo.InvariantCulture),
+        displayName,
+        username);
+```
+
+- [ ] **Step 3: Replace schedule updates**
+
+Build `SessionBatchViewModel` as before, then call:
+
+```csharp
+await messenger.UpdateScheduleAsync(
+    new PlatformScheduleMessage(
+        group,
+        view,
+        new PlatformMessageRef(PlatformKind.Telegram, group.ExternalGroupId, group.ExternalThreadId, messageId.ToString(System.Globalization.CultureInfo.InvariantCulture))),
+    ct);
+```
+
+- [ ] **Step 4: Replace interaction replies**
+
+Use:
+
+```csharp
+await messenger.AnswerInteractionAsync(
+    new PlatformInteractionReply(command.CallbackQueryId, text, showAlert: false),
+    ct);
+```
+
+- [ ] **Step 5: Replace direct notifications**
+
+`DirectSessionNotificationSender` should become a small compatibility service over `IPlatformMessenger`:
+
+```csharp
+await messenger.SendPrivateMessageAsync(
+    new PlatformPrivateMessage(
+        new PlatformUser(PlatformKind.Telegram, recipient.TelegramId.ToString(CultureInfo.InvariantCulture), recipient.DisplayName, null),
+        htmlText),
+    ct);
+```
+
+- [ ] **Step 6: Replace calendar file sending**
+
+`ExportCalendarHandler` builds the same ICS bytes and calls `SendCalendarFileAsync`, preserving the subscription URL button as a `PlatformMessageAction`.
+
+- [ ] **Step 7: Run target source tests**
+
+Run:
+
+```powershell
+dotnet test tests/GmRelay.Bot.Tests/GmRelay.Bot.Tests.csproj --filter TelegramPlatformMessengerSourceTests
+```
+
+Expected: `Passed`.
+
+### Task 6: Regression Tests
+
+**Files:**
+- Existing tests only unless a compiler failure exposes a missing using or changed behavior.
+
+- [ ] **Step 1: Run rendering and routing tests**
+
+Run:
+
+```powershell
+dotnet test tests/GmRelay.Bot.Tests/GmRelay.Bot.Tests.csproj --filter "FullyQualifiedName~Rendering|FullyQualifiedName~Telegram|FullyQualifiedName~RescheduleSession"
+```
+
+Expected: `Passed`.
+
+- [ ] **Step 2: Run all tests**
+
+Run:
+
+```powershell
+dotnet test tests/GmRelay.Bot.Tests/GmRelay.Bot.Tests.csproj
+```
+
+Expected: `Passed`.
+
+- [ ] **Step 3: Build solution**
+
+Run:
+
+```powershell
+dotnet build GM-Relay.slnx
+```
+
+Expected: `Build succeeded` with warnings treated as errors.
+
+### Task 7: Version Bump
+
+**Files:**
+- Modify: `Directory.Build.props`
+- Modify: `compose.yaml`
+- Modify: `.gitea/workflows/deploy.yml`
+- Modify: `src/GmRelay.Web/Components/Layout/NavMenu.razor`
+
+- [ ] **Step 1: Update all four version locations to `2.0.1`**
+- [ ] **Step 2: Verify sync**
+
+Run:
+
+```powershell
+rg -n "2\\.0\\.0|2\\.0\\.1" Directory.Build.props compose.yaml .gitea/workflows/deploy.yml src/GmRelay.Web/Components/Layout/NavMenu.razor
+```
+
+Expected: no `2.0.0` matches in these files and `2.0.1` appears in all required locations.
+
+### Task 8: Documentation Review
+
+**Files:**
+- Review: `README.md`
+- Review: `docs/adr/002-platform-neutral-batch-rendering.md`
+
+- [ ] **Step 1: Check README and ADR for platform contract accuracy**
+- [ ] **Step 2: Update docs if they now misrepresent platform-neutral responsibilities**
+
+Expected likely doc change: README currently lists current version as `v1.15.0`, which is already inconsistent with repo version `2.0.0`. If this PR bumps to `2.0.1`, update that line to `v2.0.1`.
+
+### Task 9: Commit, PR, CI, Review, Merge, Deploy, Release
+
+**Files:**
+- Stage only files intentionally changed for issue #24.
+
+- [ ] **Step 1: Create branch**
+
+```powershell
+git checkout -b codex/refactor/issue-24-platform-messenger
+```
+
+- [ ] **Step 2: Commit**
+
+```powershell
+git add src/GmRelay.Shared/Platform src/GmRelay.Bot tests/GmRelay.Bot.Tests Directory.Build.props compose.yaml .gitea/workflows/deploy.yml src/GmRelay.Web/Components/Layout/NavMenu.razor README.md docs/adr/002-platform-neutral-batch-rendering.md
+git commit -m "refactor: add platform messenger contracts"
+```
+
+- [ ] **Step 3: Push and create PR via Gitea**
+- [ ] **Step 4: Wait for PR CI and fix failures if any**
+- [ ] **Step 5: Run code review subagent and address findings**
+- [ ] **Step 6: Merge PR after CI and review**
+- [ ] **Step 7: Monitor deploy workflow**
+- [ ] **Step 8: Create release `v2.0.1` with Russian release notes**
+- [ ] **Step 9: Close issue #24 with PR and release links**
+
+## Self-Review
+
+- Spec coverage: all issue acceptance criteria map to Shared contracts, Telegram adapter, handler source tests, and build/test verification.
+- Placeholder scan: no `TBD`, `TODO`, or "fill later" placeholders are left in this plan.
+- Type consistency: all snippets use `GmRelay.Shared.Platform`, `PlatformKind.Telegram`, `PlatformMessageRef`, and `IPlatformMessenger` consistently.
+- Scope control: inbound Telegram update parsing remains out of scope; outbound schedule/private/interaction/calendar operations are in scope.

docs/superpowers/plans/2026-05-18-platform-neutral-join-leave.md

@@ -0,0 +1,599 @@
+# Platform-Neutral Join Leave Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Implement Gitea issue #25 by making join/leave session interactions use platform-neutral command models while preserving Telegram callback behavior, seat limits, and waitlist semantics.
+
+**Architecture:** Telegram callback routing remains in `UpdateRouter`, but it becomes an adapter that converts callback data into `PlatformUser`, `PlatformGroup`, and `PlatformMessageRef` values. `JoinSessionHandler` and `LeaveSessionHandler` operate on those neutral values, persist players by `(platform, external_user_id)`, and update schedules through `IPlatformMessenger`.
+
+**Tech Stack:** .NET 10, xUnit, Dapper, Npgsql, Gitea Actions.
+
+---
+
+## Issue Context
+
+- Issue: `#25 refactor: obobshchit JoinSession i LeaveSession pod platform-neutral interactions`
+- Labels: `area:bot`, `area:platform`, `area:shared`, `platform:multi`, `type:refactor`
+- Version bump: patch, `2.1.0` -> `2.1.1`. The issue is labeled refactor, not breaking; do not use a major bump without explicit approval.
+- Existing untracked file: `CLAUDE.md`; do not stage or modify it.
+
+## File Map
+
+- Create: `tests/GmRelay.Bot.Tests/Features/Sessions/CreateSession/PlatformNeutralSessionInteractionCommandTests.cs`
+  - Reflection tests proving join/leave command records expose neutral properties and no Telegram-specific identity/message fields.
+- Create: `tests/GmRelay.Bot.Tests/Features/Sessions/CreateSession/PlatformNeutralSessionInteractionSqlTests.cs`
+  - Source-level regression tests for handler SQL and messenger boundaries.
+- Modify: `tests/GmRelay.Bot.Tests/Infrastructure/Database/PlatformIdentityMigrationTests.cs`
+  - Add a migration test for nullable legacy `players.telegram_id`, required for non-Telegram player inserts.
+- Create: `src/GmRelay.Bot/Migrations/V017__allow_platform_neutral_players.sql`
+  - Drop `NOT NULL` from legacy Telegram-only player columns.
+- Modify: `src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs`
+  - Change `JoinSessionCommand` to neutral properties and query/upsert players by platform identity.
+- Modify: `src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs`
+  - Change `LeaveSessionCommand` to neutral properties and find participants by platform identity.
+- Modify: `src/GmRelay.Bot/Infrastructure/Telegram/UpdateRouter.cs`
+  - Convert Telegram callback data into neutral command values using `TelegramPlatformIds`.
+- Modify: version files after implementation:
+  - `Directory.Build.props`
+  - `compose.yaml`
+  - `.gitea/workflows/deploy.yml`
+  - `src/GmRelay.Web/Components/Layout/NavMenu.razor`
+
+## Task 1: RED - Command Model Tests
+
+**Files:**
+- Create: `tests/GmRelay.Bot.Tests/Features/Sessions/CreateSession/PlatformNeutralSessionInteractionCommandTests.cs`
+
+- [ ] **Step 1: Write failing command-shape tests**
+
+```csharp
+using GmRelay.Bot.Features.Sessions.CreateSession;
+using GmRelay.Shared.Platform;
+
+namespace GmRelay.Bot.Tests.Features.Sessions.CreateSession;
+
+public sealed class PlatformNeutralSessionInteractionCommandTests
+{
+    [Fact]
+    public void JoinSessionCommand_ShouldExposePlatformNeutralInteractionContext()
+    {
+        AssertProperty<JoinSessionCommand>("SessionId", typeof(Guid));
+        AssertProperty<JoinSessionCommand>("User", typeof(PlatformUser));
+        AssertProperty<JoinSessionCommand>("InteractionId", typeof(string));
+        AssertProperty<JoinSessionCommand>("Group", typeof(PlatformGroup));
+        AssertProperty<JoinSessionCommand>("ScheduleMessage", typeof(PlatformMessageRef));
+        AssertNoTelegramSpecificProperties<JoinSessionCommand>();
+    }
+
+    [Fact]
+    public void LeaveSessionCommand_ShouldExposePlatformNeutralInteractionContext()
+    {
+        AssertProperty<LeaveSessionCommand>("SessionId", typeof(Guid));
+        AssertProperty<LeaveSessionCommand>("User", typeof(PlatformUser));
+        AssertProperty<LeaveSessionCommand>("InteractionId", typeof(string));
+        AssertProperty<LeaveSessionCommand>("Group", typeof(PlatformGroup));
+        AssertProperty<LeaveSessionCommand>("ScheduleMessage", typeof(PlatformMessageRef));
+        AssertNoTelegramSpecificProperties<LeaveSessionCommand>();
+    }
+
+    private static void AssertProperty<T>(string name, Type expectedType)
+    {
+        var property = Assert.Single(typeof(T).GetProperties(), property => property.Name == name);
+
+        Assert.Equal(expectedType, property.PropertyType);
+    }
+
+    private static void AssertNoTelegramSpecificProperties<T>()
+    {
+        var names = typeof(T).GetProperties().Select(property => property.Name).ToArray();
+
+        Assert.DoesNotContain(names, name => name.Contains("Telegram", StringComparison.Ordinal));
+        Assert.DoesNotContain("ChatId", names);
+        Assert.DoesNotContain("MessageId", names);
+        Assert.DoesNotContain("TelegramUserId", names);
+        Assert.DoesNotContain("TelegramUsername", names);
+    }
+}
+```
+
+- [ ] **Step 2: Verify RED**
+
+Run:
+
+```powershell
+dotnet test .\tests\GmRelay.Bot.Tests\GmRelay.Bot.Tests.csproj --filter PlatformNeutralSessionInteractionCommandTests
+```
+
+Expected: FAIL because `JoinSessionCommand` and `LeaveSessionCommand` still expose `TelegramUserId`, `ChatId`, and `MessageId`, and do not expose `User`, `Group`, or `ScheduleMessage`.
+
+## Task 2: RED - SQL and Boundary Tests
+
+**Files:**
+- Create: `tests/GmRelay.Bot.Tests/Features/Sessions/CreateSession/PlatformNeutralSessionInteractionSqlTests.cs`
+- Modify: `tests/GmRelay.Bot.Tests/Infrastructure/Database/PlatformIdentityMigrationTests.cs`
+
+- [ ] **Step 1: Write failing handler source tests**
+
+```csharp
+namespace GmRelay.Bot.Tests.Features.Sessions.CreateSession;
+
+public sealed class PlatformNeutralSessionInteractionSqlTests
+{
+    [Fact]
+    public async Task JoinSessionHandler_ShouldPersistPlayersByPlatformIdentity()
+    {
+        var handler = await ReadRepositoryFileAsync("src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs");
+
+        Assert.Contains("platform, external_user_id", handler, StringComparison.Ordinal);
+        Assert.Contains("ON CONFLICT (platform, external_user_id)", handler, StringComparison.Ordinal);
+        Assert.Contains("ExternalUserId", handler, StringComparison.Ordinal);
+        Assert.Contains("ExternalUsername", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("TelegramPlatformIds.", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("command.TelegramUserId", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("command.TelegramUsername", handler, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public async Task LeaveSessionHandler_ShouldFindParticipantsByPlatformIdentity()
+    {
+        var handler = await ReadRepositoryFileAsync("src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs");
+
+        Assert.Contains("p.platform = @Platform", handler, StringComparison.Ordinal);
+        Assert.Contains("p.external_user_id = @ExternalUserId", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("p.telegram_id = @TelegramUserId", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("TelegramPlatformIds.", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("command.TelegramUserId", handler, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public async Task SessionInteractionHandlers_ShouldUpdateSchedulesThroughCommandMessageReference()
+    {
+        var joinHandler = await ReadRepositoryFileAsync("src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs");
+        var leaveHandler = await ReadRepositoryFileAsync("src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs");
+
+        Assert.Contains("new PlatformScheduleMessage(", joinHandler, StringComparison.Ordinal);
+        Assert.Contains("command.Group", joinHandler, StringComparison.Ordinal);
+        Assert.Contains("command.ScheduleMessage", joinHandler, StringComparison.Ordinal);
+        Assert.Contains("new PlatformScheduleMessage(", leaveHandler, StringComparison.Ordinal);
+        Assert.Contains("command.Group", leaveHandler, StringComparison.Ordinal);
+        Assert.Contains("command.ScheduleMessage", leaveHandler, StringComparison.Ordinal);
+    }
+
+    private static async Task<string> ReadRepositoryFileAsync(string relativePath)
+    {
+        var directory = new DirectoryInfo(AppContext.BaseDirectory);
+        while (directory is not null)
+        {
+            var candidate = Path.Combine(directory.FullName, relativePath);
+            if (File.Exists(candidate))
+            {
+                return await File.ReadAllTextAsync(candidate);
+            }
+
+            directory = directory.Parent;
+        }
+
+        throw new FileNotFoundException($"Could not locate repository file '{relativePath}'.");
+    }
+}
+```
+
+- [ ] **Step 2: Add failing migration assertion**
+
+Append to `PlatformIdentityMigrationTests`:
+
+```csharp
+[Fact]
+public async Task MigrationV017_ShouldAllowPlayersWithoutLegacyTelegramId()
+{
+    var migration = await ReadRepositoryFileAsync("src/GmRelay.Bot/Migrations/V017__allow_platform_neutral_players.sql");
+
+    Assert.Contains("ALTER TABLE players", migration, StringComparison.Ordinal);
+    Assert.Contains("telegram_id DROP NOT NULL", migration, StringComparison.Ordinal);
+}
+```
+
+- [ ] **Step 3: Verify RED**
+
+Run:
+
+```powershell
+dotnet test .\tests\GmRelay.Bot.Tests\GmRelay.Bot.Tests.csproj --filter "PlatformNeutralSessionInteractionSqlTests|MigrationV017_ShouldAllowPlayersWithoutLegacyTelegramId"
+```
+
+Expected: FAIL because handlers still use Telegram-specific properties and the V017 migration file does not exist.
+
+## Task 3: GREEN - Add Migration
+
+**Files:**
+- Create: `src/GmRelay.Bot/Migrations/V017__allow_platform_neutral_players.sql`
+
+- [ ] **Step 1: Create the migration**
+
+```sql
+-- =============================================================
+-- V017: Allow platform-neutral players
+-- =============================================================
+-- Legacy Telegram identity columns remain for backward compatibility,
+-- but non-Telegram platform users do not have Telegram ids.
+-- =============================================================
+
+ALTER TABLE players
+    ALTER COLUMN telegram_id DROP NOT NULL;
+```
+
+- [ ] **Step 2: Verify migration test turns green**
+
+Run:
+
+```powershell
+dotnet test .\tests\GmRelay.Bot.Tests\GmRelay.Bot.Tests.csproj --filter MigrationV017_ShouldAllowPlayersWithoutLegacyTelegramId
+```
+
+Expected: PASS.
+
+## Task 4: GREEN - Refactor JoinSessionCommand and Handler
+
+**Files:**
+- Modify: `src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs`
+
+- [ ] **Step 1: Replace command record**
+
+Replace the existing `JoinSessionCommand` declaration with:
+
+```csharp
+public sealed record JoinSessionCommand(
+    Guid SessionId,
+    PlatformUser User,
+    string InteractionId,
+    PlatformGroup Group,
+    PlatformMessageRef ScheduleMessage);
+```
+
+- [ ] **Step 2: Replace player upsert**
+
+Use platform identity parameters:
+
+```csharp
+var platform = command.User.Platform.ToString();
+var legacyTelegramId = command.User.Platform == PlatformKind.Telegram
+    ? long.Parse(command.User.ExternalUserId, CultureInfo.InvariantCulture)
+    : (long?)null;
+var legacyTelegramUsername = command.User.Platform == PlatformKind.Telegram
+    ? command.User.ExternalUsername
+    : null;
+
+var playerId = await connection.ExecuteScalarAsync<Guid>(
+    @"INSERT INTO players (telegram_id, display_name, telegram_username, platform, external_user_id, external_username)
+      VALUES (@LegacyTelegramId, @Name, @LegacyTelegramUsername, @Platform, @ExternalUserId, @ExternalUsername)
+      ON CONFLICT (platform, external_user_id)
+      WHERE platform IS NOT NULL AND external_user_id IS NOT NULL
+      DO UPDATE
+      SET display_name = EXCLUDED.display_name,
+          telegram_username = COALESCE(EXCLUDED.telegram_username, players.telegram_username),
+          platform = EXCLUDED.platform,
+          external_user_id = EXCLUDED.external_user_id,
+          external_username = EXCLUDED.external_username
+      RETURNING id;",
+    new
+    {
+        LegacyTelegramId = legacyTelegramId,
+        Name = command.User.DisplayName,
+        LegacyTelegramUsername = legacyTelegramUsername,
+        Platform = platform,
+        command.User.ExternalUserId,
+        command.User.ExternalUsername
+    },
+    transaction);
+```
+
+Add `using System.Globalization;` at the top.
+
+- [ ] **Step 3: Update participant display query**
+
+Change the participant projection to prefer platform-neutral username:
+
+```sql
+COALESCE(p.external_username, p.telegram_username) as TelegramUsername
+```
+
+- [ ] **Step 4: Update schedule message and interaction reply usage**
+
+Use:
+
+```csharp
+await messenger.UpdateScheduleAsync(
+    new PlatformScheduleMessage(
+        command.Group,
+        view,
+        command.ScheduleMessage),
+    ct);
+```
+
+and:
+
+```csharp
+private Task AnswerAsync(string interactionId, string text, CancellationToken ct) =>
+    messenger.AnswerInteractionAsync(new PlatformInteractionReply(interactionId, text), ct);
+```
+
+Replace all `command.CallbackQueryId` calls with `command.InteractionId`.
+
+- [ ] **Step 5: Verify command and SQL tests for join**
+
+Run:
+
+```powershell
+dotnet test .\tests\GmRelay.Bot.Tests\GmRelay.Bot.Tests.csproj --filter "JoinSessionCommand_ShouldExposePlatformNeutralInteractionContext|JoinSessionHandler_ShouldPersistPlayersByPlatformIdentity"
+```
+
+Expected: PASS for join-focused tests.
+
+## Task 5: GREEN - Refactor LeaveSessionCommand and Handler
+
+**Files:**
+- Modify: `src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs`
+
+- [ ] **Step 1: Replace command record**
+
+Replace the existing `LeaveSessionCommand` declaration with:
+
+```csharp
+public sealed record LeaveSessionCommand(
+    Guid SessionId,
+    PlatformUser User,
+    string InteractionId,
+    PlatformGroup Group,
+    PlatformMessageRef ScheduleMessage);
+```
+
+- [ ] **Step 2: Replace participant lookup**
+
+Use platform identity instead of Telegram id:
+
+```csharp
+var platform = command.User.Platform.ToString();
+
+var participant = await connection.QuerySingleOrDefaultAsync<LeaveSessionParticipantDto>(
+    """
+    SELECT sp.id AS ParticipantRowId,
+           p.display_name AS DisplayName,
+           sp.registration_status AS RegistrationStatus
+    FROM session_participants sp
+    JOIN players p ON p.id = sp.player_id
+    WHERE sp.session_id = @SessionId
+      AND p.platform = @Platform
+      AND p.external_user_id = @ExternalUserId
+      AND sp.is_gm = false
+    FOR UPDATE OF sp
+    """,
+    new { command.SessionId, Platform = platform, command.User.ExternalUserId },
+    transaction);
+```
+
+- [ ] **Step 3: Update participant display query**
+
+Change the participant projection to:
+
+```sql
+COALESCE(p.external_username, p.telegram_username) AS TelegramUsername
+```
+
+- [ ] **Step 4: Update schedule message and interaction reply usage**
+
+Use:
+
+```csharp
+await messenger.UpdateScheduleAsync(
+    new PlatformScheduleMessage(
+        command.Group,
+        view,
+        command.ScheduleMessage),
+    ct);
+```
+
+Replace all `command.CallbackQueryId` calls with `command.InteractionId`.
+
+- [ ] **Step 5: Verify leave tests**
+
+Run:
+
+```powershell
+dotnet test .\tests\GmRelay.Bot.Tests\GmRelay.Bot.Tests.csproj --filter "LeaveSessionCommand_ShouldExposePlatformNeutralInteractionContext|LeaveSessionHandler_ShouldFindParticipantsByPlatformIdentity|SessionInteractionHandlers_ShouldUpdateSchedulesThroughCommandMessageReference"
+```
+
+Expected: PASS.
+
+## Task 6: GREEN - Convert Telegram Router to Neutral Commands
+
+**Files:**
+- Modify: `src/GmRelay.Bot/Infrastructure/Telegram/UpdateRouter.cs`
+
+- [ ] **Step 1: Add local conversion values in `HandleCallbackQueryAsync`**
+
+After parsing `action`, add:
+
+```csharp
+var user = TelegramPlatformIds.User(
+    query.From.Id,
+    query.From.FirstName + (string.IsNullOrEmpty(query.From.LastName) ? "" : $" {query.From.LastName}"),
+    query.From.Username);
+var group = TelegramPlatformIds.Group(message.Chat.Id, message.MessageThreadId, message.Chat.Title);
+var scheduleMessage = TelegramPlatformIds.Message(message.Chat.Id, message.MessageThreadId, message.MessageId);
+```
+
+- [ ] **Step 2: Update join command construction**
+
+```csharp
+var command = new JoinSessionCommand(
+    SessionId: joinSessionId,
+    User: user,
+    InteractionId: query.Id,
+    Group: group,
+    ScheduleMessage: scheduleMessage);
+```
+
+- [ ] **Step 3: Update leave command construction**
+
+```csharp
+var command = new LeaveSessionCommand(
+    SessionId: leaveSessionId,
+    User: user,
+    InteractionId: query.Id,
+    Group: group,
+    ScheduleMessage: scheduleMessage);
+```
+
+- [ ] **Step 4: Verify compile**
+
+Run:
+
+```powershell
+dotnet test .\tests\GmRelay.Bot.Tests\GmRelay.Bot.Tests.csproj --filter PlatformNeutralSessionInteractionCommandTests
+```
+
+Expected: PASS.
+
+## Task 7: REFACTOR - Clean Up and Full Test Pass
+
+**Files:**
+- Modify only files already listed if cleanup is needed.
+
+- [ ] **Step 1: Remove now-unused Telegram handler imports**
+
+Check `JoinSessionHandler.cs` and `LeaveSessionHandler.cs` for unused:
+
+```csharp
+using GmRelay.Bot.Infrastructure.Telegram;
+```
+
+Remove it from handlers if no longer needed.
+
+- [ ] **Step 2: Run focused tests**
+
+```powershell
+dotnet test .\tests\GmRelay.Bot.Tests\GmRelay.Bot.Tests.csproj --filter "PlatformNeutralSessionInteractionCommandTests|PlatformNeutralSessionInteractionSqlTests|PlatformIdentityMigrationTests"
+```
+
+Expected: PASS.
+
+- [ ] **Step 3: Run full test suite**
+
+```powershell
+dotnet test .\GM-Relay.slnx
+```
+
+Expected: PASS.
+
+- [ ] **Step 4: Build solution**
+
+```powershell
+dotnet build .\GM-Relay.slnx
+```
+
+Expected: PASS.
+
+## Task 8: Version Bump
+
+**Files:**
+- Modify: `Directory.Build.props`
+- Modify: `compose.yaml`
+- Modify: `.gitea/workflows/deploy.yml`
+- Modify: `src/GmRelay.Web/Components/Layout/NavMenu.razor`
+
+- [ ] **Step 1: Update version from `2.1.0` to `2.1.1`**
+
+Expected exact replacements:
+
+```xml
+<Version>2.1.1</Version>
+```
+
+```yaml
+VERSION: 2.1.1
+```
+
+```yaml
+image: git.codeanddice.ru/toutsu/gmrelay-bot:2.1.1
+image: git.codeanddice.ru/toutsu/gmrelay-web:2.1.1
+```
+
+```razor
+<div class="nav-version">v2.1.1</div>
+```
+
+- [ ] **Step 2: Verify synchronized versions**
+
+Run:
+
+```powershell
+rg "<Version>|image: git.codeanddice.ru/toutsu/gmrelay-|VERSION:|nav-version" Directory.Build.props compose.yaml .gitea\workflows\deploy.yml src\GmRelay.Web\Components\Layout\NavMenu.razor
+```
+
+Expected: all project image/app/deploy UI versions show `2.1.1`.
+
+## Task 9: PR, CI, Review, Merge, Deploy, Release
+
+**Files:**
+- No additional source changes expected.
+
+- [ ] **Step 1: Create branch after approval**
+
+```powershell
+git checkout -b refactor/issue-25-platform-neutral-join-leave
+```
+
+- [ ] **Step 2: Stage only intended files**
+
+```powershell
+git add docs/superpowers/plans/2026-05-18-platform-neutral-join-leave.md tests/GmRelay.Bot.Tests/Features/Sessions/CreateSession/PlatformNeutralSessionInteractionCommandTests.cs tests/GmRelay.Bot.Tests/Features/Sessions/CreateSession/PlatformNeutralSessionInteractionSqlTests.cs tests/GmRelay.Bot.Tests/Infrastructure/Database/PlatformIdentityMigrationTests.cs src/GmRelay.Bot/Migrations/V017__allow_platform_neutral_players.sql src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs src/GmRelay.Bot/Infrastructure/Telegram/UpdateRouter.cs Directory.Build.props compose.yaml .gitea/workflows/deploy.yml src/GmRelay.Web/Components/Layout/NavMenu.razor
+```
+
+- [ ] **Step 3: Commit**
+
+```powershell
+git commit -m "refactor: make session join leave platform-neutral"
+```
+
+- [ ] **Step 4: Push and create Gitea PR**
+
+```powershell
+git push -u origin refactor/issue-25-platform-neutral-join-leave
+```
+
+PR title:
+
+```text
+refactor: make session join leave platform-neutral
+```
+
+PR body:
+
+```markdown
+## Summary
+- Closes #25.
+- Converts join/leave session interaction commands from Telegram-specific fields to platform-neutral `PlatformUser`, `PlatformGroup`, and `PlatformMessageRef`.
+- Persists and looks up session participants by `(platform, external_user_id)`.
+- Keeps Telegram callback data and schedule update behavior intact.
+
+## Test plan
+- `dotnet test .\tests\GmRelay.Bot.Tests\GmRelay.Bot.Tests.csproj --filter "PlatformNeutralSessionInteractionCommandTests|PlatformNeutralSessionInteractionSqlTests|PlatformIdentityMigrationTests"`
+- `dotnet test .\GM-Relay.slnx`
+- `dotnet build .\GM-Relay.slnx`
+
+## Workflow
+- [ ] CI passes
+- [ ] Code review approved
+- [ ] Deployed
+- [ ] Release published
+```
+
+- [ ] **Step 5: Watch CI, request review, merge, deploy, release**
+
+Use Gitea MCP for PR creation, CI polling, review, merge, deploy monitoring, and release `v2.1.1`. Close issue #25 after release and add a comment linking the PR and release.
+
+## Self-Review
+
+- Spec coverage: issue scope is covered by neutral command records, Telegram adapter conversion, platform identity SQL, messenger-based schedule updates, and tests.
+- Placeholder scan: no `TBD`, `TODO`, or "fill later" steps remain.
+- Type consistency: commands consistently use `PlatformUser User`, `string InteractionId`, `PlatformGroup Group`, and `PlatformMessageRef ScheduleMessage`.

src/GmRelay.Bot/Features/Notifications/DirectSessionNotificationSender.cs

@@ -1,12 +1,12 @@
-using Telegram.Bot;
-using Telegram.Bot.Types.Enums;
+using GmRelay.Bot.Infrastructure.Telegram;
+using GmRelay.Shared.Platform;
 
 namespace GmRelay.Bot.Features.Notifications;
 
 public sealed record DirectNotificationRecipient(long TelegramId, string DisplayName);
 
 public sealed class DirectSessionNotificationSender(
-    ITelegramBotClient bot,
+    IPlatformMessenger messenger,
     ILogger<DirectSessionNotificationSender> logger)
 {
     public async Task SendAsync(
@@ -20,11 +20,11 @@ public sealed class DirectSessionNotificationSender(
         {
             try
             {
-                await bot.SendMessage(
-                    chatId: recipient.TelegramId,
-                    text: htmlText,
-                    parseMode: ParseMode.Html,
-                    cancellationToken: ct);
+                await messenger.SendPrivateMessageAsync(
+                    new PlatformPrivateMessage(
+                        TelegramPlatformIds.User(recipient.TelegramId, recipient.DisplayName),
+                        htmlText),
+                    ct);
             }
             catch (Exception ex)
             {

src/GmRelay.Bot/Features/Sessions/CreateSession/CancelSessionHandler.cs

@@ -1,10 +1,9 @@
 using Dapper;
 using GmRelay.Bot.Features.Notifications;
 using GmRelay.Shared.Domain;
+using GmRelay.Shared.Platform;
 using GmRelay.Shared.Rendering;
 using Npgsql;
-using Telegram.Bot;
-using Telegram.Bot.Types;
 using GmRelay.Bot.Infrastructure.Telegram;
 
 namespace GmRelay.Bot.Features.Sessions.CreateSession;
@@ -22,7 +21,7 @@ internal sealed record CancelSessionInfoDto(string Title, Guid BatchId, int? Bat
 
 public sealed class CancelSessionHandler(
     NpgsqlDataSource dataSource,
-    ITelegramBotClient bot,
+    IPlatformMessenger messenger,
     DirectSessionNotificationSender directSender,
     ILogger<CancelSessionHandler> logger)
 {
@@ -52,13 +51,13 @@ public sealed class CancelSessionHandler(
 
         if (session == null)
         {
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, "Сессия не найдена.", cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, "Сессия не найдена.", ct);
             return;
         }
 
         if (!session.CanManage)
         {
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, "Только owner или co-GM может отменять сессию.", showAlert: true, cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, "Только owner или co-GM может отменять сессию.", ct, showAlert: true);
             return;
         }
 
@@ -105,27 +104,24 @@ public sealed class CancelSessionHandler(
 
         // 4. Перерисовываем сообщение
         var view = SessionBatchViewBuilder.Build(session.Title, batchSessions.ToList(), batchParticipants.ToList());
-        var renderResult = TelegramSessionBatchRenderer.Render(view);
 
         try
         {
-            await BatchMessageEditor.EditBatchMessageAsync(
-                bot,
-                chatId: command.ChatId,
-                messageId: session.BatchMessageId ?? command.MessageId,
-                text: renderResult.Text,
-                replyMarkup: renderResult.Markup,
+            var messageId = session.BatchMessageId ?? command.MessageId;
+            await messenger.UpdateScheduleAsync(
+                new PlatformScheduleMessage(
+                    TelegramPlatformIds.Group(command.ChatId, command.MessageThreadId),
+                    view,
+                    TelegramPlatformIds.Message(command.ChatId, command.MessageThreadId, messageId)),
                 ct);
 
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, "Сессия отменена!", cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, "Сессия отменена!", ct);
 
             // Опционально: написать отдельное сообщение в чат
-            await bot.SendMessage(
-                chatId: command.ChatId,
-                messageThreadId: command.MessageThreadId,
-                text: $"❌ <b>Внимание!</b> Сессия \"{System.Net.WebUtility.HtmlEncode(session.Title)}\" отменена.",
-                parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
-                cancellationToken: ct);
+            await messenger.SendGroupMessageAsync(
+                TelegramPlatformIds.Group(command.ChatId, command.MessageThreadId),
+                $"❌ <b>Внимание!</b> Сессия \"{System.Net.WebUtility.HtmlEncode(session.Title)}\" отменена.",
+                ct);
 
             var mode = SessionNotificationModeExtensions.FromDatabaseValue(session.NotificationMode);
             if (mode.ShouldSendDirectMessages())
@@ -141,7 +137,10 @@ public sealed class CancelSessionHandler(
         catch (Exception ex)
         {
             logger.LogError(ex, "Failed to update batch message after cancelling session {SessionId}", command.SessionId);
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, "Ошибка при обновлении сообщения.", cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, "Ошибка при обновлении сообщения.", ct);
         }
     }
+
+    private Task AnswerAsync(string callbackQueryId, string text, CancellationToken ct, bool showAlert = false) =>
+        messenger.AnswerInteractionAsync(new PlatformInteractionReply(callbackQueryId, text, showAlert), ct);
 }

src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs

@@ -1,28 +1,25 @@
+using System.Globalization;
 using Dapper;
 using Npgsql;
-using Telegram.Bot;
-using Telegram.Bot.Types;
 using GmRelay.Shared.Domain;
+using GmRelay.Shared.Platform;
 using GmRelay.Shared.Rendering;
-using GmRelay.Bot.Infrastructure.Telegram;
 
 namespace GmRelay.Bot.Features.Sessions.CreateSession;
 
 public sealed record JoinSessionCommand(
     Guid SessionId,
-    long TelegramUserId,
-    string DisplayName,
-    string? TelegramUsername,
-    string CallbackQueryId,
-    long ChatId,
-    int MessageId);
+    PlatformUser User,
+    string InteractionId,
+    PlatformGroup Group,
+    PlatformMessageRef ScheduleMessage);
 
 // DTOs for AOT compilation
 internal sealed record JoinSessionBatchDto(Guid BatchId, string Title, int? MaxPlayers);
 
 public sealed class JoinSessionHandler(
     NpgsqlDataSource dataSource,
-    ITelegramBotClient bot,
+    IPlatformMessenger messenger,
     ILogger<JoinSessionHandler> logger)
 {
     public async Task HandleAsync(JoinSessionCommand command, CancellationToken ct)
@@ -34,17 +31,35 @@ public sealed class JoinSessionHandler(
         try
         {
             // 1. Убеждаемся, что игрок есть в базе
+            var platform = command.User.Platform.ToString();
+            var legacyTelegramId = command.User.Platform == PlatformKind.Telegram
+                ? long.Parse(command.User.ExternalUserId, CultureInfo.InvariantCulture)
+                : (long?)null;
+            var legacyTelegramUsername = command.User.Platform == PlatformKind.Telegram
+                ? command.User.ExternalUsername
+                : null;
+
             var playerId = await connection.ExecuteScalarAsync<Guid>(
                 @"INSERT INTO players (telegram_id, display_name, telegram_username, platform, external_user_id, external_username)
-                  VALUES (@TgId, @Name, @Username, 'Telegram', @TgId::TEXT, @Username)
-                  ON CONFLICT (telegram_id) DO UPDATE
+                  VALUES (@LegacyTelegramId, @Name, @LegacyTelegramUsername, @Platform, @ExternalUserId, @ExternalUsername)
+                  ON CONFLICT (platform, external_user_id)
+                  WHERE platform IS NOT NULL AND external_user_id IS NOT NULL
+                  DO UPDATE
                   SET display_name = EXCLUDED.display_name,
-                      telegram_username = EXCLUDED.telegram_username,
-                      platform = COALESCE(players.platform, 'Telegram'),
-                      external_user_id = COALESCE(players.external_user_id, EXCLUDED.telegram_id::TEXT),
-                      external_username = COALESCE(players.external_username, EXCLUDED.telegram_username)
+                      telegram_username = COALESCE(EXCLUDED.telegram_username, players.telegram_username),
+                      platform = EXCLUDED.platform,
+                      external_user_id = EXCLUDED.external_user_id,
+                      external_username = EXCLUDED.external_username
                   RETURNING id;",
-                new { TgId = command.TelegramUserId, Name = command.DisplayName, Username = command.TelegramUsername },
+                new
+                {
+                    LegacyTelegramId = legacyTelegramId,
+                    Name = command.User.DisplayName,
+                    LegacyTelegramUsername = legacyTelegramUsername,
+                    Platform = platform,
+                    command.User.ExternalUserId,
+                    command.User.ExternalUsername
+                },
                 transaction);
 
             // 2. Блокируем сессию на время расчета мест, чтобы параллельные нажатия не переполнили состав.
@@ -59,7 +74,7 @@ public sealed class JoinSessionHandler(
             if (batchInfo is null)
             {
                 await transaction.RollbackAsync(ct);
-                await bot.AnswerCallbackQuery(command.CallbackQueryId, "Сессия не найдена.", cancellationToken: ct);
+                await AnswerAsync(command.InteractionId, "Сессия не найдена.", ct);
                 return;
             }
 
@@ -80,7 +95,7 @@ public sealed class JoinSessionHandler(
                 var alreadyText = existingRegistrationStatus == ParticipantRegistrationStatus.Waitlisted
                     ? "Вы уже в листе ожидания!"
                     : "Вы уже записаны!";
-                await bot.AnswerCallbackQuery(command.CallbackQueryId, alreadyText, cancellationToken: ct);
+                await AnswerAsync(command.InteractionId, alreadyText, ct);
                 return;
             }
 
@@ -114,7 +129,7 @@ public sealed class JoinSessionHandler(
             if (inserted == 0)
             {
                 await transaction.RollbackAsync(ct);
-                await bot.AnswerCallbackQuery(command.CallbackQueryId, "Вы уже записаны!", cancellationToken: ct);
+                await AnswerAsync(command.InteractionId, "Вы уже записаны!", ct);
                 return;
             }
 
@@ -129,7 +144,7 @@ public sealed class JoinSessionHandler(
             var batchParticipants = await connection.QueryAsync<ParticipantBatchDto>(
                 @"SELECT sp.session_id as SessionId,
                          p.display_name as DisplayName,
-                         p.telegram_username as TelegramUsername,
+                         COALESCE(p.external_username, p.telegram_username) as TelegramUsername,
                          sp.registration_status as RegistrationStatus
                   FROM session_participants sp
                   JOIN players p ON sp.player_id = p.id
@@ -143,20 +158,17 @@ public sealed class JoinSessionHandler(
 
             // 4. Перерисовываем сообщение
             var view = SessionBatchViewBuilder.Build(batchInfo.Title, batchSessions.ToList(), batchParticipants.ToList());
-            var renderResult = TelegramSessionBatchRenderer.Render(view);
-
-            await BatchMessageEditor.EditBatchMessageAsync(
-                bot,
-                chatId: command.ChatId,
-                messageId: command.MessageId,
-                text: renderResult.Text,
-                replyMarkup: renderResult.Markup,
+            await messenger.UpdateScheduleAsync(
+                new PlatformScheduleMessage(
+                    command.Group,
+                    view,
+                    command.ScheduleMessage),
                 ct);
 
             var callbackText = registrationStatus == ParticipantRegistrationStatus.Waitlisted
                 ? "Основной состав заполнен. Вы добавлены в лист ожидания."
                 : "Вы успешно записаны!";
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, callbackText, cancellationToken: ct);
+            await AnswerAsync(command.InteractionId, callbackText, ct);
         }
         catch (Exception ex)
         {
@@ -169,7 +181,10 @@ public sealed class JoinSessionHandler(
             var errorText = transactionCommitted
                 ? "Регистрация сохранена, но не удалось обновить сообщение расписания."
                 : "Произошла ошибка при регистрации.";
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, errorText, cancellationToken: ct);
+            await AnswerAsync(command.InteractionId, errorText, ct);
         }
     }
+
+    private Task AnswerAsync(string interactionId, string text, CancellationToken ct) =>
+        messenger.AnswerInteractionAsync(new PlatformInteractionReply(interactionId, text), ct);
 }

src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs

@@ -1,18 +1,17 @@
 using Dapper;
 using GmRelay.Shared.Domain;
+using GmRelay.Shared.Platform;
 using GmRelay.Shared.Rendering;
 using Npgsql;
-using Telegram.Bot;
-using GmRelay.Bot.Infrastructure.Telegram;
 
 namespace GmRelay.Bot.Features.Sessions.CreateSession;
 
 public sealed record LeaveSessionCommand(
     Guid SessionId,
-    long TelegramUserId,
-    string CallbackQueryId,
-    long ChatId,
-    int MessageId);
+    PlatformUser User,
+    string InteractionId,
+    PlatformGroup Group,
+    PlatformMessageRef ScheduleMessage);
 
 internal sealed record LeaveSessionInfoDto(string Title, Guid BatchId, string Status, int? MaxPlayers);
 internal sealed record LeaveSessionParticipantDto(Guid ParticipantRowId, string DisplayName, string RegistrationStatus);
@@ -20,7 +19,7 @@ internal sealed record LeaveSessionPromotionDto(Guid ParticipantRowId, string Di
 
 public sealed class LeaveSessionHandler(
     NpgsqlDataSource dataSource,
-    ITelegramBotClient bot,
+    IPlatformMessenger messenger,
     ILogger<LeaveSessionHandler> logger)
 {
     public async Task HandleAsync(LeaveSessionCommand command, CancellationToken ct)
@@ -47,17 +46,19 @@ public sealed class LeaveSessionHandler(
             if (session is null)
             {
                 await transaction.RollbackAsync(ct);
-                await bot.AnswerCallbackQuery(command.CallbackQueryId, "Сессия не найдена.", cancellationToken: ct);
+                await AnswerAsync(command.InteractionId, "Сессия не найдена.", ct);
                 return;
             }
 
             if (SessionStatus.IsCancelled(session.Status))
             {
                 await transaction.RollbackAsync(ct);
-                await bot.AnswerCallbackQuery(command.CallbackQueryId, "Сессия уже отменена.", cancellationToken: ct);
+                await AnswerAsync(command.InteractionId, "Сессия уже отменена.", ct);
                 return;
             }
 
+            var platform = command.User.Platform.ToString();
+
             var participant = await connection.QuerySingleOrDefaultAsync<LeaveSessionParticipantDto>(
                 """
                 SELECT sp.id AS ParticipantRowId,
@@ -66,17 +67,18 @@ public sealed class LeaveSessionHandler(
                 FROM session_participants sp
                 JOIN players p ON p.id = sp.player_id
                 WHERE sp.session_id = @SessionId
-                  AND p.telegram_id = @TelegramUserId
+                  AND p.platform = @Platform
+                  AND p.external_user_id = @ExternalUserId
                   AND sp.is_gm = false
                 FOR UPDATE OF sp
                 """,
-                new { command.SessionId, command.TelegramUserId },
+                new { command.SessionId, Platform = platform, command.User.ExternalUserId },
                 transaction);
 
             if (participant is null)
             {
                 await transaction.RollbackAsync(ct);
-                await bot.AnswerCallbackQuery(command.CallbackQueryId, "Вы не записаны на эту сессию.", cancellationToken: ct);
+                await AnswerAsync(command.InteractionId, "Вы не записаны на эту сессию.", ct);
                 return;
             }
 
@@ -170,7 +172,7 @@ public sealed class LeaveSessionHandler(
                 """
                 SELECT sp.session_id AS SessionId,
                        p.display_name AS DisplayName,
-                       p.telegram_username AS TelegramUsername,
+                       COALESCE(p.external_username, p.telegram_username) AS TelegramUsername,
                        sp.registration_status AS RegistrationStatus
                 FROM session_participants sp
                 JOIN players p ON sp.player_id = p.id
@@ -185,14 +187,11 @@ public sealed class LeaveSessionHandler(
             transactionCommitted = true;
 
             var view = SessionBatchViewBuilder.Build(session.Title, batchSessions, batchParticipants);
-            var renderResult = TelegramSessionBatchRenderer.Render(view);
-
-            await BatchMessageEditor.EditBatchMessageAsync(
-                bot,
-                chatId: command.ChatId,
-                messageId: command.MessageId,
-                text: renderResult.Text,
-                replyMarkup: renderResult.Markup,
+            await messenger.UpdateScheduleAsync(
+                new PlatformScheduleMessage(
+                    command.Group,
+                    view,
+                    command.ScheduleMessage),
                 ct);
 
             var callbackText = participant.RegistrationStatus == ParticipantRegistrationStatus.Waitlisted
@@ -201,7 +200,7 @@ public sealed class LeaveSessionHandler(
                     ? "Вы отписались от сессии."
                     : $"Вы отписались от сессии. Место получил(а) {promotedDisplayName}.";
 
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, callbackText, cancellationToken: ct);
+            await AnswerAsync(command.InteractionId, callbackText, ct);
         }
         catch (Exception ex)
         {
@@ -214,7 +213,10 @@ public sealed class LeaveSessionHandler(
             var errorText = transactionCommitted
                 ? "Запись снята, но не удалось обновить сообщение расписания."
                 : "Произошла ошибка при отмене записи.";
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, errorText, cancellationToken: ct);
+            await AnswerAsync(command.InteractionId, errorText, ct);
         }
     }
+
+    private Task AnswerAsync(string interactionId, string text, CancellationToken ct) =>
+        messenger.AnswerInteractionAsync(new PlatformInteractionReply(interactionId, text), ct);
 }

src/GmRelay.Bot/Features/Sessions/CreateSession/PromoteWaitlistedPlayerHandler.cs

@@ -1,8 +1,8 @@
 using Dapper;
 using GmRelay.Shared.Domain;
+using GmRelay.Shared.Platform;
 using GmRelay.Shared.Rendering;
 using Npgsql;
-using Telegram.Bot;
 using GmRelay.Bot.Infrastructure.Telegram;
 
 namespace GmRelay.Bot.Features.Sessions.CreateSession;
@@ -19,7 +19,7 @@ internal sealed record WaitlistedParticipantDto(Guid ParticipantRowId, string Di
 
 public sealed class PromoteWaitlistedPlayerHandler(
     NpgsqlDataSource dataSource,
-    ITelegramBotClient bot,
+    IPlatformMessenger messenger,
     ILogger<PromoteWaitlistedPlayerHandler> logger)
 {
     public async Task HandleAsync(PromoteWaitlistedPlayerCommand command, CancellationToken ct)
@@ -53,14 +53,14 @@ public sealed class PromoteWaitlistedPlayerHandler(
             if (session is null)
             {
                 await transaction.RollbackAsync(ct);
-                await bot.AnswerCallbackQuery(command.CallbackQueryId, "Сессия не найдена.", cancellationToken: ct);
+                await AnswerAsync(command.CallbackQueryId, "Сессия не найдена.", ct);
                 return;
             }
 
             if (!session.CanManage)
             {
                 await transaction.RollbackAsync(ct);
-                await bot.AnswerCallbackQuery(command.CallbackQueryId, "Только owner или co-GM может поднимать игроков из листа ожидания.", showAlert: true, cancellationToken: ct);
+                await AnswerAsync(command.CallbackQueryId, "Только owner или co-GM может поднимать игроков из листа ожидания.", ct, showAlert: true);
                 return;
             }
 
@@ -89,14 +89,14 @@ public sealed class PromoteWaitlistedPlayerHandler(
             if (waitlistedParticipants == 0)
             {
                 await transaction.RollbackAsync(ct);
-                await bot.AnswerCallbackQuery(command.CallbackQueryId, "Лист ожидания пуст.", cancellationToken: ct);
+                await AnswerAsync(command.CallbackQueryId, "Лист ожидания пуст.", ct);
                 return;
             }
 
             if (!SessionCapacityRules.CanPromoteWaitlistedPlayer(session.MaxPlayers, activeParticipants, waitlistedParticipants))
             {
                 await transaction.RollbackAsync(ct);
-                await bot.AnswerCallbackQuery(command.CallbackQueryId, "Нет свободных мест. Увеличьте лимит перед повышением игрока.", showAlert: true, cancellationToken: ct);
+                await AnswerAsync(command.CallbackQueryId, "Нет свободных мест. Увеличьте лимит перед повышением игрока.", ct, showAlert: true);
                 return;
             }
 
@@ -165,17 +165,15 @@ public sealed class PromoteWaitlistedPlayerHandler(
             transactionCommitted = true;
 
             var view = SessionBatchViewBuilder.Build(session.Title, batchSessions, batchParticipants);
-            var renderResult = TelegramSessionBatchRenderer.Render(view);
-
-            await BatchMessageEditor.EditBatchMessageAsync(
-                bot,
-                chatId: command.ChatId,
-                messageId: session.BatchMessageId ?? command.MessageId,
-                text: renderResult.Text,
-                replyMarkup: renderResult.Markup,
+            var messageId = session.BatchMessageId ?? command.MessageId;
+            await messenger.UpdateScheduleAsync(
+                new PlatformScheduleMessage(
+                    TelegramPlatformIds.Group(command.ChatId),
+                    view,
+                    TelegramPlatformIds.Message(command.ChatId, threadId: null, messageId)),
                 ct);
 
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, $"{promoted.DisplayName} переведен(а) в основной состав.", cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, $"{promoted.DisplayName} переведен(а) в основной состав.", ct);
         }
         catch (Exception ex)
         {
@@ -188,7 +186,10 @@ public sealed class PromoteWaitlistedPlayerHandler(
             var errorText = transactionCommitted
                 ? "Игрок повышен, но не удалось обновить сообщение расписания."
                 : "Ошибка при обновлении листа ожидания.";
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, errorText, cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, errorText, ct);
         }
     }
+
+    private Task AnswerAsync(string callbackQueryId, string text, CancellationToken ct, bool showAlert = false) =>
+        messenger.AnswerInteractionAsync(new PlatformInteractionReply(callbackQueryId, text, showAlert), ct);
 }

src/GmRelay.Bot/Features/Sessions/ExportCalendar/ExportCalendarHandler.cs

@@ -1,11 +1,11 @@
 using System.Text;
 using Dapper;
+using GmRelay.Bot.Infrastructure.Telegram;
 using GmRelay.Shared.Domain;
+using GmRelay.Shared.Platform;
 using Microsoft.Extensions.Configuration;
 using Npgsql;
-using Telegram.Bot;
 using Telegram.Bot.Types;
-using Telegram.Bot.Types.ReplyMarkups;
 
 namespace GmRelay.Bot.Features.Sessions.ExportCalendar;
 
@@ -13,7 +13,7 @@ internal sealed record CalendarSessionDto(Guid Id, string Title, DateTime Schedu
 
 public sealed class ExportCalendarHandler(
     NpgsqlDataSource dataSource,
-    ITelegramBotClient botClient,
+    IPlatformMessenger messenger,
     IConfiguration configuration)
 {
     public async Task HandleAsync(Message message, CancellationToken cancellationToken)
@@ -34,10 +34,10 @@ public sealed class ExportCalendarHandler(
 
         if (sessionsList.Count == 0)
         {
-            await botClient.SendMessage(
-                chatId: message.Chat.Id,
-                text: "📭 У этой группы нет запланированных сессий для экспорта.",
-                cancellationToken: cancellationToken);
+            await messenger.SendGroupMessageAsync(
+                TelegramPlatformIds.Group(message.Chat.Id, message.MessageThreadId),
+                "📭 У этой группы нет запланированных сессий для экспорта.",
+                cancellationToken);
             return;
         }
 
@@ -63,9 +63,7 @@ public sealed class ExportCalendarHandler(
         sb.AppendLine("END:VCALENDAR");
 
         var bytes = Encoding.UTF8.GetBytes(sb.ToString());
-        using var stream = new MemoryStream(bytes);
 
-        var inputFile = InputFile.FromStream(stream, "schedule.ics");
 
         // Create calendar subscription
         string? subscriptionUrl = null;
@@ -93,20 +91,23 @@ public sealed class ExportCalendarHandler(
             }
         }
 
-        var replyMarkup = subscriptionUrl is not null
-            ? new InlineKeyboardMarkup(new[]
+        var actions = subscriptionUrl is not null
+            ? new[]
             {
-                new[] { InlineKeyboardButton.WithUrl("🔗 Подписаться на календарь", subscriptionUrl) }
-            })
-            : null;
+                new PlatformMessageAction(
+                    "calendar-subscription",
+                    "🔗 Подписаться на календарь",
+                    subscriptionUrl)
+            }
+            : Array.Empty<PlatformMessageAction>();
 
-        await botClient.SendDocument(
-             chatId: message.Chat.Id,
-             document: inputFile,
-             caption: "📅 <b>Ваш календарь игр!</b>\nОткройте файл на устройстве, чтобы добавить события в свой календарь.",
-             parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
-             replyMarkup: replyMarkup,
-             messageThreadId: message.MessageThreadId,
-             cancellationToken: cancellationToken);
+        await messenger.SendCalendarFileAsync(
+            new PlatformCalendarFile(
+                TelegramPlatformIds.Group(message.Chat.Id, message.MessageThreadId),
+                "schedule.ics",
+                bytes,
+                "📅 <b>Ваш календарь игр!</b>\nОткройте файл на устройстве, чтобы добавить события в свой календарь.",
+                actions),
+            cancellationToken);
     }
 }

src/GmRelay.Bot/Features/Sessions/RescheduleSession/HandleRescheduleTimeInputHandler.cs

@@ -1,6 +1,7 @@
 using Dapper;
 using GmRelay.Bot.Features.Notifications;
 using GmRelay.Shared.Domain;
+using GmRelay.Shared.Platform;
 using GmRelay.Shared.Rendering;
 using Npgsql;
 using Telegram.Bot;
@@ -33,6 +34,7 @@ internal sealed record VoteParticipantDto(
 public sealed class HandleRescheduleTimeInputHandler(
     NpgsqlDataSource dataSource,
     ITelegramBotClient bot,
+    IPlatformMessenger messenger,
     DirectSessionNotificationSender directSender,
     ILogger<HandleRescheduleTimeInputHandler> logger)
 {
@@ -83,12 +85,10 @@ public sealed class HandleRescheduleTimeInputHandler(
         // 2. Parse voting input
         if (!RescheduleVotingInput.TryParse(text, DateTimeOffset.UtcNow, out var votingInput, out var parseError))
         {
-            await bot.SendMessage(
-                chatId: chatId,
-                messageThreadId: proposal.ThreadId,
-                text: $"⚠️ {parseError}\n\nИспользуйте формат:\n<code>25.04.2026 19:30\n26.04.2026 18:00\nДедлайн: 25.04.2026 12:00</code>",
-                parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
-                cancellationToken: ct);
+            await messenger.SendGroupMessageAsync(
+                TelegramPlatformIds.Group(chatId, proposal.ThreadId),
+                $"⚠️ {parseError}\n\nИспользуйте формат:\n<code>25.04.2026 19:30\n26.04.2026 18:00\nДедлайн: 25.04.2026 12:00</code>",
+                ct);
             return true;
         }
 
@@ -243,12 +243,10 @@ public sealed class HandleRescheduleTimeInputHandler(
 
         await transaction.CommitAsync(ct);
 
-        await bot.SendMessage(
-            chatId: chatId,
-            messageThreadId: proposal.ThreadId,
-            text: $"✅ Сессия «{proposal.Title}» перенесена!\n\n📅 Новое время: <b>{newTime.ToOffset(TimeSpan.FromHours(3)).ToString("d MMMM yyyy, HH:mm", System.Globalization.CultureInfo.GetCultureInfo("ru-RU"))}</b> (МСК)\n\n<i>Участников нет — голосование не требуется.</i>",
-            parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
-            cancellationToken: ct);
+        await messenger.SendGroupMessageAsync(
+            TelegramPlatformIds.Group(chatId, proposal.ThreadId),
+            $"✅ Сессия «{proposal.Title}» перенесена!\n\n📅 Новое время: <b>{newTime.ToOffset(TimeSpan.FromHours(3)).ToString("d MMMM yyyy, HH:mm", System.Globalization.CultureInfo.GetCultureInfo("ru-RU"))}</b> (МСК)\n\n<i>Участников нет — голосование не требуется.</i>",
+            ct);
 
         // Re-render batch message with updated time
         await TryUpdateBatchMessage(proposal, ct);
@@ -383,14 +381,12 @@ public sealed class HandleRescheduleTimeInputHandler(
             if (proposal.BatchMessageId.HasValue)
             {
                 var view = SessionBatchViewBuilder.Build(proposal.Title, batchSessions, batchParticipants);
-                var renderResult = TelegramSessionBatchRenderer.Render(view);
 
-                await BatchMessageEditor.EditBatchMessageAsync(
-                    bot,
-                    chatId: proposal.TelegramChatId,
-                    messageId: proposal.BatchMessageId.Value,
-                    text: renderResult.Text,
-                    replyMarkup: renderResult.Markup,
+                await messenger.UpdateScheduleAsync(
+                    new PlatformScheduleMessage(
+                        TelegramPlatformIds.Group(proposal.TelegramChatId, proposal.ThreadId),
+                        view,
+                        TelegramPlatformIds.Message(proposal.TelegramChatId, proposal.ThreadId, proposal.BatchMessageId.Value)),
                     ct);
             }
             else

src/GmRelay.Bot/Features/Sessions/RescheduleSession/HandleRescheduleVoteHandler.cs

@@ -1,5 +1,6 @@
 using Dapper;
 using GmRelay.Shared.Domain;
+using GmRelay.Shared.Platform;
 using Npgsql;
 using Telegram.Bot;
 
@@ -22,6 +23,7 @@ internal sealed record VoteProposalDto(
 public sealed class HandleRescheduleVoteHandler(
     NpgsqlDataSource dataSource,
     ITelegramBotClient bot,
+    IPlatformMessenger messenger,
     ILogger<HandleRescheduleVoteHandler> logger)
 {
     public async Task HandleAsync(HandleRescheduleVoteCommand command, CancellationToken ct)
@@ -46,20 +48,13 @@ public sealed class HandleRescheduleVoteHandler(
 
         if (proposal is null)
         {
-            await bot.AnswerCallbackQuery(
-                command.CallbackQueryId,
-                "Голосование уже завершено или не найдено.",
-                cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, "Голосование уже завершено или не найдено.", ct);
             return;
         }
 
         if (proposal.VotingDeadlineAt <= DateTimeOffset.UtcNow)
         {
-            await bot.AnswerCallbackQuery(
-                command.CallbackQueryId,
-                "Дедлайн уже прошёл. Результаты скоро будут применены.",
-                showAlert: true,
-                cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, "Дедлайн уже прошёл. Результаты скоро будут применены.", ct, showAlert: true);
             return;
         }
 
@@ -78,10 +73,7 @@ public sealed class HandleRescheduleVoteHandler(
 
         if (playerId is null)
         {
-            await bot.AnswerCallbackQuery(
-                command.CallbackQueryId,
-                "Вы не являетесь участником этой сессии.",
-                cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, "Вы не являетесь участником этой сессии.", ct);
             return;
         }
 
@@ -169,9 +161,9 @@ public sealed class HandleRescheduleVoteHandler(
             logger.LogWarning(ex, "Failed to update reschedule vote message for proposal {ProposalId}", proposal.Id);
         }
 
-        await bot.AnswerCallbackQuery(
-            command.CallbackQueryId,
-            "Ваш голос учтён. До дедлайна его можно изменить.",
-            cancellationToken: ct);
+        await AnswerAsync(command.CallbackQueryId, "Ваш голос учтён. До дедлайна его можно изменить.", ct);
     }
+
+    private Task AnswerAsync(string callbackQueryId, string text, CancellationToken ct, bool showAlert = false) =>
+        messenger.AnswerInteractionAsync(new PlatformInteractionReply(callbackQueryId, text, showAlert), ct);
 }

src/GmRelay.Bot/Features/Sessions/RescheduleSession/InitiateRescheduleHandler.cs

@@ -1,7 +1,8 @@
 using Dapper;
+using GmRelay.Bot.Infrastructure.Telegram;
 using GmRelay.Shared.Domain;
+using GmRelay.Shared.Platform;
 using Npgsql;
-using Telegram.Bot;
 
 namespace GmRelay.Bot.Features.Sessions.RescheduleSession;
 
@@ -28,7 +29,7 @@ internal sealed record RescheduleSessionInfoDto(string Title, bool CanManage);
 /// </summary>
 public sealed class InitiateRescheduleHandler(
     NpgsqlDataSource dataSource,
-    ITelegramBotClient bot,
+    IPlatformMessenger messenger,
     ILogger<InitiateRescheduleHandler> logger)
 {
     public async Task HandleAsync(InitiateRescheduleCommand command, CancellationToken ct)
@@ -53,14 +54,13 @@ public sealed class InitiateRescheduleHandler(
 
         if (session is null)
         {
-            await bot.AnswerCallbackQuery(command.CallbackQueryId, "Сессия не найдена.", cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, "Сессия не найдена.", ct);
             return;
         }
 
         if (!session.CanManage)
         {
-            await bot.AnswerCallbackQuery(command.CallbackQueryId,
-                "Только owner или co-GM может переносить сессию.", showAlert: true, cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, "Только owner или co-GM может переносить сессию.", ct, showAlert: true);
             return;
         }
 
@@ -76,8 +76,7 @@ public sealed class InitiateRescheduleHandler(
 
         if (hasActive)
         {
-            await bot.AnswerCallbackQuery(command.CallbackQueryId,
-                "Уже есть активный запрос на перенос этой сессии.", showAlert: true, cancellationToken: ct);
+            await AnswerAsync(command.CallbackQueryId, "Уже есть активный запрос на перенос этой сессии.", ct, showAlert: true);
             return;
         }
 
@@ -92,23 +91,28 @@ public sealed class InitiateRescheduleHandler(
         logger.LogInformation("Reschedule initiated for session {SessionId} by GM {GmId}", command.SessionId, command.TelegramUserId);
 
         // 4. Prompt GM in chat
-        await bot.AnswerCallbackQuery(command.CallbackQueryId,
-            "Введите 2-3 варианта времени и дедлайн голосования.", cancellationToken: ct);
+        await AnswerAsync(command.CallbackQueryId, "Введите 2-3 варианта времени и дедлайн голосования.", ct);
 
-        await bot.SendMessage(
-            chatId: command.ChatId,
-            messageThreadId: command.MessageThreadId,
-            text: $"""
-                ⏰ Укажите 2-3 варианта времени для сессии «{session.Title}» и дедлайн голосования.
+        var prompt = string.Join(
+            "\n",
+            new[]
+            {
+                $"⏰ Укажите 2-3 варианта времени для сессии «{session.Title}» и дедлайн голосования.",
+                "",
+                "Формат:",
+                "<code>25.04.2026 19:30",
+                "26.04.2026 18:00",
+                "Дедлайн: 25.04.2026 12:00</code>",
+                "",
+                "Дедлайн должен быть в будущем и раньше первого предложенного времени."
+            });
 
-                Формат:
-                <code>25.04.2026 19:30
-                26.04.2026 18:00
-                Дедлайн: 25.04.2026 12:00</code>
-
-                Дедлайн должен быть в будущем и раньше первого предложенного времени.
-                """,
-            parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
-            cancellationToken: ct);
+        await messenger.SendGroupMessageAsync(
+            TelegramPlatformIds.Group(command.ChatId, command.MessageThreadId),
+            prompt,
+            ct);
     }
+
+    private Task AnswerAsync(string callbackQueryId, string text, CancellationToken ct, bool showAlert = false) =>
+        messenger.AnswerInteractionAsync(new PlatformInteractionReply(callbackQueryId, text, showAlert), ct);
 }

src/GmRelay.Bot/Features/Sessions/RescheduleSession/RescheduleVotingDeadlineService.cs

@@ -2,6 +2,7 @@ using Dapper;
 using GmRelay.Bot.Features.Notifications;
 using GmRelay.Bot.Infrastructure.Scheduling;
 using GmRelay.Shared.Domain;
+using GmRelay.Shared.Platform;
 using GmRelay.Shared.Rendering;
 using Npgsql;
 using Telegram.Bot;
@@ -26,6 +27,7 @@ internal sealed record DueRescheduleProposalDto(
 public sealed class RescheduleVotingDeadlineService(
     NpgsqlDataSource dataSource,
     ITelegramBotClient bot,
+    IPlatformMessenger messenger,
     DirectSessionNotificationSender directSender,
     ISystemClock clock,
     ILogger<RescheduleVotingDeadlineService> logger) : BackgroundService
@@ -312,24 +314,20 @@ public sealed class RescheduleVotingDeadlineService(
             if (proposal.BatchMessageId.HasValue)
             {
                 var view = SessionBatchViewBuilder.Build(proposal.Title, batchSessions, batchParticipants);
-                var renderResult = TelegramSessionBatchRenderer.Render(view);
 
-                await BatchMessageEditor.EditBatchMessageAsync(
-                    bot,
-                    chatId: proposal.TelegramChatId,
-                    messageId: proposal.BatchMessageId.Value,
-                    text: renderResult.Text,
-                    replyMarkup: renderResult.Markup,
+                await messenger.UpdateScheduleAsync(
+                    new PlatformScheduleMessage(
+                        TelegramPlatformIds.Group(proposal.TelegramChatId, proposal.ThreadId),
+                        view,
+                        TelegramPlatformIds.Message(proposal.TelegramChatId, proposal.ThreadId, proposal.BatchMessageId.Value)),
                     ct);
             }
             else
             {
-                await bot.SendMessage(
-                    chatId: proposal.TelegramChatId,
-                    messageThreadId: proposal.ThreadId,
-                    text: $"📣 Расписание обновлено после голосования за перенос сессии «{System.Net.WebUtility.HtmlEncode(proposal.Title)}».",
-                    parseMode: ParseMode.Html,
-                    cancellationToken: ct);
+                await messenger.SendGroupMessageAsync(
+                    TelegramPlatformIds.Group(proposal.TelegramChatId, proposal.ThreadId),
+                    $"📣 Расписание обновлено после голосования за перенос сессии «{System.Net.WebUtility.HtmlEncode(proposal.Title)}».",
+                    ct);
             }
         }
         catch (Exception ex)

src/GmRelay.Bot/Infrastructure/Telegram/TelegramPlatformIds.cs

@@ -0,0 +1,29 @@
+using System.Globalization;
+using GmRelay.Shared.Platform;
+
+namespace GmRelay.Bot.Infrastructure.Telegram;
+
+internal static class TelegramPlatformIds
+{
+    public static PlatformGroup Group(long chatId, int? threadId = null, string? displayName = null) =>
+        new(
+            PlatformKind.Telegram,
+            chatId.ToString(CultureInfo.InvariantCulture),
+            displayName ?? "Telegram chat",
+            ExternalChannelId: chatId.ToString(CultureInfo.InvariantCulture),
+            ExternalThreadId: threadId?.ToString(CultureInfo.InvariantCulture));
+
+    public static PlatformUser User(long telegramId, string displayName, string? username = null) =>
+        new(
+            PlatformKind.Telegram,
+            telegramId.ToString(CultureInfo.InvariantCulture),
+            displayName,
+            username);
+
+    public static PlatformMessageRef Message(long chatId, int? threadId, int messageId) =>
+        new(
+            PlatformKind.Telegram,
+            chatId.ToString(CultureInfo.InvariantCulture),
+            threadId?.ToString(CultureInfo.InvariantCulture),
+            messageId.ToString(CultureInfo.InvariantCulture));
+}

src/GmRelay.Bot/Infrastructure/Telegram/TelegramPlatformMessenger.cs

@@ -0,0 +1,196 @@
+using System.Globalization;
+using GmRelay.Shared.Platform;
+using Telegram.Bot;
+using Telegram.Bot.Types;
+using Telegram.Bot.Types.Enums;
+using Telegram.Bot.Types.ReplyMarkups;
+
+namespace GmRelay.Bot.Infrastructure.Telegram;
+
+public sealed class TelegramPlatformMessenger(
+    ITelegramBotClient bot,
+    ILogger<TelegramPlatformMessenger> logger) : IPlatformMessenger
+{
+    public async Task<PlatformMessageRef> SendScheduleAsync(PlatformScheduleMessage message, CancellationToken ct)
+    {
+        EnsureTelegram(message.Group.Platform);
+
+        var chatId = ParseLong(message.Group.ExternalGroupId);
+        var threadId = ParseNullableInt(message.Group.ExternalThreadId);
+        var renderResult = TelegramSessionBatchRenderer.Render(message.View);
+        Message sentMessage;
+
+        if (!string.IsNullOrWhiteSpace(message.ImageReference) && renderResult.Text.Length <= 1024)
+        {
+            try
+            {
+                sentMessage = await bot.SendPhoto(
+                    chatId: chatId,
+                    messageThreadId: threadId,
+                    photo: InputFile.FromString(message.ImageReference),
+                    caption: renderResult.Text,
+                    parseMode: ParseMode.Html,
+                    replyMarkup: renderResult.Markup,
+                    cancellationToken: ct);
+            }
+            catch (Exception ex)
+            {
+                logger.LogWarning(ex, "Failed to send Telegram schedule image for group {ExternalGroupId}", message.Group.ExternalGroupId);
+                sentMessage = await SendScheduleTextMessage(chatId, threadId, renderResult.Text, renderResult.Markup, ct);
+            }
+        }
+        else
+        {
+            if (!string.IsNullOrWhiteSpace(message.ImageReference))
+            {
+                await TrySendScheduleImageOnly(chatId, threadId, message.View.Title, message.ImageReference, ct);
+            }
+
+            sentMessage = await SendScheduleTextMessage(chatId, threadId, renderResult.Text, renderResult.Markup, ct);
+        }
+
+        return new PlatformMessageRef(
+            PlatformKind.Telegram,
+            message.Group.ExternalGroupId,
+            message.Group.ExternalThreadId,
+            sentMessage.MessageId.ToString(CultureInfo.InvariantCulture));
+    }
+
+    public async Task UpdateScheduleAsync(PlatformScheduleMessage message, CancellationToken ct)
+    {
+        EnsureTelegram(message.Group.Platform);
+        var existingMessage = message.ExistingMessage;
+        if (existingMessage is null)
+        {
+            throw new ArgumentException("Existing schedule message reference is required.", nameof(message));
+        }
+
+        EnsureTelegram(existingMessage.Platform);
+        if (!string.Equals(message.Group.ExternalGroupId, existingMessage.ExternalGroupId, StringComparison.Ordinal) ||
+            !string.Equals(message.Group.ExternalThreadId, existingMessage.ExternalThreadId, StringComparison.Ordinal))
+        {
+            throw new ArgumentException("Existing schedule message reference must match the schedule group.", nameof(message));
+        }
+
+        var renderResult = TelegramSessionBatchRenderer.Render(message.View);
+        await BatchMessageEditor.EditBatchMessageAsync(
+            bot,
+            chatId: ParseLong(existingMessage.ExternalGroupId),
+            messageId: ParseInt(existingMessage.ExternalMessageId),
+            text: renderResult.Text,
+            replyMarkup: renderResult.Markup,
+            ct);
+    }
+
+    public Task SendGroupMessageAsync(PlatformGroup group, string htmlText, CancellationToken ct)
+    {
+        EnsureTelegram(group.Platform);
+        return bot.SendMessage(
+            chatId: ParseLong(group.ExternalGroupId),
+            messageThreadId: ParseNullableInt(group.ExternalThreadId),
+            text: htmlText,
+            parseMode: ParseMode.Html,
+            cancellationToken: ct);
+    }
+
+    public Task SendPrivateMessageAsync(PlatformPrivateMessage message, CancellationToken ct)
+    {
+        EnsureTelegram(message.Recipient.Platform);
+        return bot.SendMessage(
+            chatId: ParseLong(message.Recipient.ExternalUserId),
+            text: message.HtmlText,
+            parseMode: ParseMode.Html,
+            cancellationToken: ct);
+    }
+
+    public Task AnswerInteractionAsync(PlatformInteractionReply reply, CancellationToken ct) =>
+        bot.AnswerCallbackQuery(
+            callbackQueryId: reply.InteractionId,
+            text: reply.Text,
+            showAlert: reply.ShowAlert,
+            cancellationToken: ct);
+
+    public async Task SendCalendarFileAsync(PlatformCalendarFile file, CancellationToken ct)
+    {
+        EnsureTelegram(file.Group.Platform);
+
+        using var stream = new MemoryStream(file.Content);
+        await bot.SendDocument(
+            chatId: ParseLong(file.Group.ExternalGroupId),
+            messageThreadId: ParseNullableInt(file.Group.ExternalThreadId),
+            document: InputFile.FromStream(stream, file.FileName),
+            caption: file.CaptionHtml,
+            parseMode: ParseMode.Html,
+            replyMarkup: BuildActionsMarkup(file.Actions),
+            cancellationToken: ct);
+    }
+
+    private async Task<Message> SendScheduleTextMessage(
+        long chatId,
+        int? threadId,
+        string text,
+        InlineKeyboardMarkup markup,
+        CancellationToken ct) =>
+        await bot.SendMessage(
+            chatId: chatId,
+            messageThreadId: threadId,
+            text: text,
+            parseMode: ParseMode.Html,
+            replyMarkup: markup,
+            cancellationToken: ct);
+
+    private async Task TrySendScheduleImageOnly(
+        long chatId,
+        int? threadId,
+        string title,
+        string imageReference,
+        CancellationToken ct)
+    {
+        try
+        {
+            await bot.SendPhoto(
+                chatId: chatId,
+                messageThreadId: threadId,
+                photo: InputFile.FromString(imageReference),
+                caption: $"🎲 {System.Net.WebUtility.HtmlEncode(title)}",
+                parseMode: ParseMode.Html,
+                cancellationToken: ct);
+        }
+        catch (Exception ex)
+        {
+            logger.LogWarning(ex, "Failed to send Telegram schedule image for chat {ChatId}", chatId);
+        }
+    }
+
+    private static InlineKeyboardMarkup? BuildActionsMarkup(IReadOnlyList<PlatformMessageAction> actions)
+    {
+        if (actions.Count == 0)
+        {
+            return null;
+        }
+
+        return new InlineKeyboardMarkup(
+            actions.Select(action => new[]
+            {
+                Uri.TryCreate(action.Payload, UriKind.Absolute, out var uri) &&
+                (uri.Scheme == Uri.UriSchemeHttp || uri.Scheme == Uri.UriSchemeHttps)
+                    ? InlineKeyboardButton.WithUrl(action.Label, action.Payload)
+                    : InlineKeyboardButton.WithCallbackData(action.Label, action.Payload)
+            }));
+    }
+
+    private static void EnsureTelegram(PlatformKind platform)
+    {
+        if (platform != PlatformKind.Telegram)
+        {
+            throw new NotSupportedException($"Telegram messenger cannot send messages for platform {platform}.");
+        }
+    }
+
+    private static long ParseLong(string value) => long.Parse(value, CultureInfo.InvariantCulture);
+
+    private static int ParseInt(string value) => int.Parse(value, CultureInfo.InvariantCulture);
+
+    private static int? ParseNullableInt(string? value) =>
+        string.IsNullOrWhiteSpace(value) ? null : int.Parse(value, CultureInfo.InvariantCulture);
+}

src/GmRelay.Bot/Infrastructure/Telegram/UpdateRouter.cs

@@ -69,17 +69,21 @@ public sealed class UpdateRouter(
 
         var parts = data.Split(':', 3);
         var action = parts[0];
+        var user = TelegramPlatformIds.User(
+            query.From.Id,
+            query.From.FirstName + (string.IsNullOrEmpty(query.From.LastName) ? "" : $" {query.From.LastName}"),
+            query.From.Username);
+        var group = TelegramPlatformIds.Group(message.Chat.Id, message.MessageThreadId, message.Chat.Title);
+        var scheduleMessage = TelegramPlatformIds.Message(message.Chat.Id, message.MessageThreadId, message.MessageId);
 
         if (action == "join_session" && parts.Length >= 2 && Guid.TryParse(parts[1], out var joinSessionId))
         {
             var command = new JoinSessionCommand(
                 SessionId: joinSessionId,
-                TelegramUserId: query.From.Id,
-                DisplayName: query.From.FirstName + (string.IsNullOrEmpty(query.From.LastName) ? "" : $" {query.From.LastName}"),
-                TelegramUsername: query.From.Username,
-                CallbackQueryId: query.Id,
-                ChatId: message.Chat.Id,
-                MessageId: message.MessageId);
+                User: user,
+                InteractionId: query.Id,
+                Group: group,
+                ScheduleMessage: scheduleMessage);
 
             await joinSessionHandler.HandleAsync(command, ct);
             return;
@@ -89,10 +93,10 @@ public sealed class UpdateRouter(
         {
             var command = new LeaveSessionCommand(
                 SessionId: leaveSessionId,
-                TelegramUserId: query.From.Id,
-                CallbackQueryId: query.Id,
-                ChatId: message.Chat.Id,
-                MessageId: message.MessageId);
+                User: user,
+                InteractionId: query.Id,
+                Group: group,
+                ScheduleMessage: scheduleMessage);
 
             await leaveSessionHandler.HandleAsync(command, ct);
             return;

src/GmRelay.Bot/Migrations/V017__allow_platform_neutral_players.sql

@@ -0,0 +1,9 @@
+-- =============================================================
+-- V017: Allow platform-neutral players
+-- =============================================================
+-- Legacy Telegram identity columns remain for backward compatibility,
+-- but non-Telegram platform users do not have Telegram ids.
+-- =============================================================
+
+ALTER TABLE players
+    ALTER COLUMN telegram_id DROP NOT NULL;

src/GmRelay.Bot/Program.cs

@@ -10,6 +10,7 @@ using GmRelay.Bot.Infrastructure.Health;
 using GmRelay.Bot.Infrastructure.Logging;
 using GmRelay.Bot.Infrastructure.Scheduling;
 using GmRelay.Bot.Infrastructure.Telegram;
+using GmRelay.Shared.Platform;
 using Npgsql;
 using Telegram.Bot;
 
@@ -50,6 +51,7 @@ builder.Services.AddSingleton<ITelegramBotClient>(sp =>
     return new TelegramBotClient(token);
 });
 builder.Services.AddSingleton<ITelegramUpdateSource, TelegramUpdateSource>();
+builder.Services.AddSingleton<IPlatformMessenger, TelegramPlatformMessenger>();
 
 // ── Feature handlers (explicit registration — AOT safe) ──────────────
 builder.Services.AddSingleton<SendConfirmationHandler>();

src/GmRelay.Shared/Platform/IPlatformMessenger.cs

@@ -0,0 +1,16 @@
+namespace GmRelay.Shared.Platform;
+
+public interface IPlatformMessenger
+{
+    Task<PlatformMessageRef> SendScheduleAsync(PlatformScheduleMessage message, CancellationToken ct);
+
+    Task UpdateScheduleAsync(PlatformScheduleMessage message, CancellationToken ct);
+
+    Task SendGroupMessageAsync(PlatformGroup group, string htmlText, CancellationToken ct);
+
+    Task SendPrivateMessageAsync(PlatformPrivateMessage message, CancellationToken ct);
+
+    Task AnswerInteractionAsync(PlatformInteractionReply reply, CancellationToken ct);
+
+    Task SendCalendarFileAsync(PlatformCalendarFile file, CancellationToken ct);
+}

src/GmRelay.Shared/Platform/PlatformGroup.cs

@@ -0,0 +1,8 @@
+namespace GmRelay.Shared.Platform;
+
+public sealed record PlatformGroup(
+    PlatformKind Platform,
+    string ExternalGroupId,
+    string DisplayName,
+    string? ExternalChannelId = null,
+    string? ExternalThreadId = null);

src/GmRelay.Shared/Platform/PlatformKind.cs

@@ -0,0 +1,8 @@
+namespace GmRelay.Shared.Platform;
+
+public enum PlatformKind
+{
+    Telegram = 0,
+    Discord = 1,
+    Max = 2
+}

src/GmRelay.Shared/Platform/PlatformMessageContracts.cs

@@ -0,0 +1,36 @@
+using GmRelay.Shared.Rendering;
+
+namespace GmRelay.Shared.Platform;
+
+public sealed record PlatformMessageRef(
+    PlatformKind Platform,
+    string ExternalGroupId,
+    string? ExternalThreadId,
+    string ExternalMessageId);
+
+public sealed record PlatformMessageAction(
+    string Key,
+    string Label,
+    string Payload);
+
+public sealed record PlatformScheduleMessage(
+    PlatformGroup Group,
+    SessionBatchViewModel View,
+    PlatformMessageRef? ExistingMessage,
+    string? ImageReference = null);
+
+public sealed record PlatformPrivateMessage(
+    PlatformUser Recipient,
+    string HtmlText);
+
+public sealed record PlatformInteractionReply(
+    string InteractionId,
+    string Text,
+    bool ShowAlert = false);
+
+public sealed record PlatformCalendarFile(
+    PlatformGroup Group,
+    string FileName,
+    byte[] Content,
+    string CaptionHtml,
+    IReadOnlyList<PlatformMessageAction> Actions);

src/GmRelay.Shared/Platform/PlatformUser.cs

@@ -0,0 +1,7 @@
+namespace GmRelay.Shared.Platform;
+
+public sealed record PlatformUser(
+    PlatformKind Platform,
+    string ExternalUserId,
+    string DisplayName,
+    string? ExternalUsername);

src/GmRelay.Web/Components/App.razor

@@ -10,7 +10,7 @@
     <ResourcePreloader />
     <link rel="preconnect" href="https://fonts.googleapis.com" />
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
-    <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap" rel="stylesheet" />
+    <link href="https://fonts.googleapis.com/css2?family=Cinzel+Decorative:wght@400;700&family=Cinzel:wght@400;600;700&family=Jura:wght@400;500;600;700&display=swap" rel="stylesheet" />
     <link rel="stylesheet" href="@Assets["app.css"]" />
     <link rel="stylesheet" href="@Assets["GmRelay.Web.styles.css"]" />
     <script src="https://telegram.org/js/telegram-web-app.js"></script>

src/GmRelay.Web/Components/Layout/MainLayout.razor.css

@@ -30,8 +30,9 @@
 
 /* === Error UI === */
 #blazor-error-ui {
-    background: var(--bg-secondary);
-    border-top: 1px solid var(--border-color);
+    background: var(--status-danger-bg);
+    color: var(--status-danger);
+    border-top: 1px solid rgba(239, 68, 68, 0.15);
     bottom: 0;
     box-shadow: 0 -4px 16px rgba(0, 0, 0, 0.3);
     box-sizing: border-box;
@@ -41,8 +42,9 @@
     position: fixed;
     width: 100%;
     z-index: 1000;
-    color: var(--text-secondary);
     font-size: 0.875rem;
+    font-family: 'Jura', sans-serif;
+    font-weight: 500;
 }
 
     #blazor-error-ui .reload {

src/GmRelay.Web/Components/Layout/NavMenu.razor

@@ -56,7 +56,7 @@
                     </button>
                 </form>
 
-                <div class="nav-version">v2.0.0</div>
+                <div class="nav-version">v2.1.1</div>
             </div>
         </Authorized>
         <NotAuthorized>

src/GmRelay.Web/Components/Layout/NavMenu.razor.css

@@ -23,12 +23,11 @@
 }
 
 .nav-brand-text {
+    font-family: 'Cinzel Decorative', 'Cinzel', serif;
     font-size: 1.125rem;
     font-weight: 700;
-    background: var(--accent-gradient);
-    -webkit-background-clip: text;
-    -webkit-text-fill-color: transparent;
-    background-clip: text;
+    letter-spacing: 0.04em;
+    color: var(--text-primary);
 }
 
 .nav-toggle {
@@ -87,9 +86,10 @@
 }
 
 .nav-section ::deep .nav-item.active {
-    background: rgba(124, 58, 237, 0.15);
-    color: var(--accent-primary);
-    border: 1px solid rgba(124, 58, 237, 0.2);
+    background: linear-gradient(135deg, rgba(139, 92, 246, 0.15) 0%, rgba(34, 211, 238, 0.08) 100%);
+    color: var(--text-accent);
+    border: 1px solid rgba(139, 92, 246, 0.25);
+    box-shadow: 0 0 12px rgba(139, 92, 246, 0.1);
 }
 
 .nav-icon {
@@ -145,7 +145,7 @@
     border: 1px solid transparent;
     border-radius: var(--radius-sm);
     color: var(--text-muted);
-    font-family: 'Inter', sans-serif;
+    font-family: 'Jura', sans-serif;
     font-size: 0.8125rem;
     cursor: pointer;
     transition: all var(--transition-normal);

tests/GmRelay.Bot.Tests/Features/Sessions/CreateSession/PlatformNeutralSessionInteractionCommandTests.cs

@@ -0,0 +1,47 @@
+using GmRelay.Bot.Features.Sessions.CreateSession;
+using GmRelay.Shared.Platform;
+
+namespace GmRelay.Bot.Tests.Features.Sessions.CreateSession;
+
+public sealed class PlatformNeutralSessionInteractionCommandTests
+{
+    [Fact]
+    public void JoinSessionCommand_ShouldExposePlatformNeutralInteractionContext()
+    {
+        AssertProperty<JoinSessionCommand>("SessionId", typeof(Guid));
+        AssertProperty<JoinSessionCommand>("User", typeof(PlatformUser));
+        AssertProperty<JoinSessionCommand>("InteractionId", typeof(string));
+        AssertProperty<JoinSessionCommand>("Group", typeof(PlatformGroup));
+        AssertProperty<JoinSessionCommand>("ScheduleMessage", typeof(PlatformMessageRef));
+        AssertNoTelegramSpecificProperties<JoinSessionCommand>();
+    }
+
+    [Fact]
+    public void LeaveSessionCommand_ShouldExposePlatformNeutralInteractionContext()
+    {
+        AssertProperty<LeaveSessionCommand>("SessionId", typeof(Guid));
+        AssertProperty<LeaveSessionCommand>("User", typeof(PlatformUser));
+        AssertProperty<LeaveSessionCommand>("InteractionId", typeof(string));
+        AssertProperty<LeaveSessionCommand>("Group", typeof(PlatformGroup));
+        AssertProperty<LeaveSessionCommand>("ScheduleMessage", typeof(PlatformMessageRef));
+        AssertNoTelegramSpecificProperties<LeaveSessionCommand>();
+    }
+
+    private static void AssertProperty<T>(string name, Type expectedType)
+    {
+        var property = Assert.Single(typeof(T).GetProperties(), property => property.Name == name);
+
+        Assert.Equal(expectedType, property.PropertyType);
+    }
+
+    private static void AssertNoTelegramSpecificProperties<T>()
+    {
+        var names = typeof(T).GetProperties().Select(property => property.Name).ToArray();
+
+        Assert.DoesNotContain(names, name => name.Contains("Telegram", StringComparison.Ordinal));
+        Assert.DoesNotContain("ChatId", names);
+        Assert.DoesNotContain("MessageId", names);
+        Assert.DoesNotContain("TelegramUserId", names);
+        Assert.DoesNotContain("TelegramUsername", names);
+    }
+}

tests/GmRelay.Bot.Tests/Features/Sessions/CreateSession/PlatformNeutralSessionInteractionSqlTests.cs

@@ -0,0 +1,61 @@
+namespace GmRelay.Bot.Tests.Features.Sessions.CreateSession;
+
+public sealed class PlatformNeutralSessionInteractionSqlTests
+{
+    [Fact]
+    public async Task JoinSessionHandler_ShouldPersistPlayersByPlatformIdentity()
+    {
+        var handler = await ReadRepositoryFileAsync("src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs");
+
+        Assert.Contains("platform, external_user_id", handler, StringComparison.Ordinal);
+        Assert.Contains("ON CONFLICT (platform, external_user_id)", handler, StringComparison.Ordinal);
+        Assert.Contains("ExternalUserId", handler, StringComparison.Ordinal);
+        Assert.Contains("ExternalUsername", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("TelegramPlatformIds.", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("command.TelegramUserId", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("command.TelegramUsername", handler, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public async Task LeaveSessionHandler_ShouldFindParticipantsByPlatformIdentity()
+    {
+        var handler = await ReadRepositoryFileAsync("src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs");
+
+        Assert.Contains("p.platform = @Platform", handler, StringComparison.Ordinal);
+        Assert.Contains("p.external_user_id = @ExternalUserId", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("p.telegram_id = @TelegramUserId", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("TelegramPlatformIds.", handler, StringComparison.Ordinal);
+        Assert.DoesNotContain("command.TelegramUserId", handler, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public async Task SessionInteractionHandlers_ShouldUpdateSchedulesThroughCommandMessageReference()
+    {
+        var joinHandler = await ReadRepositoryFileAsync("src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs");
+        var leaveHandler = await ReadRepositoryFileAsync("src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs");
+
+        Assert.Contains("new PlatformScheduleMessage(", joinHandler, StringComparison.Ordinal);
+        Assert.Contains("command.Group", joinHandler, StringComparison.Ordinal);
+        Assert.Contains("command.ScheduleMessage", joinHandler, StringComparison.Ordinal);
+        Assert.Contains("new PlatformScheduleMessage(", leaveHandler, StringComparison.Ordinal);
+        Assert.Contains("command.Group", leaveHandler, StringComparison.Ordinal);
+        Assert.Contains("command.ScheduleMessage", leaveHandler, StringComparison.Ordinal);
+    }
+
+    private static async Task<string> ReadRepositoryFileAsync(string relativePath)
+    {
+        var directory = new DirectoryInfo(AppContext.BaseDirectory);
+        while (directory is not null)
+        {
+            var candidate = Path.Combine(directory.FullName, relativePath);
+            if (File.Exists(candidate))
+            {
+                return await File.ReadAllTextAsync(candidate);
+            }
+
+            directory = directory.Parent;
+        }
+
+        throw new FileNotFoundException($"Could not locate repository file '{relativePath}'.");
+    }
+}

tests/GmRelay.Bot.Tests/Infrastructure/Database/PlatformIdentityMigrationTests.cs

@@ -99,6 +99,15 @@ public sealed class PlatformIdentityMigrationTests
         Assert.Contains("external_username", statsMigration, StringComparison.Ordinal);
     }
 
+    [Fact]
+    public async Task MigrationV017_ShouldAllowPlayersWithoutLegacyTelegramId()
+    {
+        var migration = await ReadRepositoryFileAsync("src/GmRelay.Bot/Migrations/V017__allow_platform_neutral_players.sql");
+
+        Assert.Contains("ALTER TABLE players", migration, StringComparison.Ordinal);
+        Assert.Contains("telegram_id DROP NOT NULL", migration, StringComparison.Ordinal);
+    }
+
     private static async Task<string> ReadRepositoryFileAsync(string relativePath)
     {
         var directory = new DirectoryInfo(AppContext.BaseDirectory);

tests/GmRelay.Bot.Tests/Infrastructure/Telegram/TelegramPlatformMessengerSourceTests.cs

@@ -0,0 +1,60 @@
+namespace GmRelay.Bot.Tests.Infrastructure.Telegram;
+
+public sealed class TelegramPlatformMessengerSourceTests
+{
+    [Fact]
+    public async Task Program_ShouldRegisterTelegramPlatformMessenger()
+    {
+        var program = await ReadRepositoryFileAsync("src/GmRelay.Bot/Program.cs");
+
+        Assert.Contains("IPlatformMessenger", program, StringComparison.Ordinal);
+        Assert.Contains("TelegramPlatformMessenger", program, StringComparison.Ordinal);
+    }
+
+    [Theory]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/CreateSession/CancelSessionHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/CreateSession/PromoteWaitlistedPlayerHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/RescheduleSession/InitiateRescheduleHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/RescheduleSession/HandleRescheduleTimeInputHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/RescheduleSession/HandleRescheduleVoteHandler.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/RescheduleSession/RescheduleVotingDeadlineService.cs")]
+    [InlineData("src/GmRelay.Bot/Features/Sessions/ExportCalendar/ExportCalendarHandler.cs")]
+    public async Task SessionFlows_ShouldUsePlatformMessengerForOutboundTelegramWork(string relativePath)
+    {
+        var source = await ReadRepositoryFileAsync(relativePath);
+
+        Assert.Contains("IPlatformMessenger", source, StringComparison.Ordinal);
+        Assert.DoesNotContain("BatchMessageEditor.EditBatchMessageAsync", source, StringComparison.Ordinal);
+        Assert.DoesNotContain(".AnswerCallbackQuery(", source, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public async Task TelegramPlatformMessenger_ShouldOwnTelegramBotClientCalls()
+    {
+        var source = await ReadRepositoryFileAsync("src/GmRelay.Bot/Infrastructure/Telegram/TelegramPlatformMessenger.cs");
+
+        Assert.Contains("ITelegramBotClient", source, StringComparison.Ordinal);
+        Assert.Contains("BatchMessageEditor.EditBatchMessageAsync", source, StringComparison.Ordinal);
+        Assert.Contains("AnswerCallbackQuery", source, StringComparison.Ordinal);
+        Assert.Contains("SendDocument", source, StringComparison.Ordinal);
+    }
+
+    private static async Task<string> ReadRepositoryFileAsync(string relativePath)
+    {
+        var directory = new DirectoryInfo(AppContext.BaseDirectory);
+        while (directory is not null)
+        {
+            var candidate = Path.Combine(directory.FullName, relativePath);
+            if (File.Exists(candidate))
+            {
+                return await File.ReadAllTextAsync(candidate);
+            }
+
+            directory = directory.Parent;
+        }
+
+        throw new FileNotFoundException($"Could not locate repository file '{relativePath}'.");
+    }
+}

tests/GmRelay.Bot.Tests/Infrastructure/Telegram/TelegramPlatformMessengerTests.cs

@@ -0,0 +1,44 @@
+using GmRelay.Bot.Infrastructure.Telegram;
+using GmRelay.Shared.Platform;
+using GmRelay.Shared.Rendering;
+using Microsoft.Extensions.Logging.Abstractions;
+
+namespace GmRelay.Bot.Tests.Infrastructure.Telegram;
+
+public sealed class TelegramPlatformMessengerTests
+{
+    [Fact]
+    public async Task UpdateScheduleAsync_ShouldRejectNonTelegramExistingMessageReference()
+    {
+        var messenger = CreateMessenger();
+        var message = new PlatformScheduleMessage(
+            new PlatformGroup(PlatformKind.Telegram, "100", "Telegram group"),
+            CreateView(),
+            new PlatformMessageRef(PlatformKind.Discord, "100", null, "200"));
+
+        await Assert.ThrowsAsync<NotSupportedException>(
+            () => messenger.UpdateScheduleAsync(message, CancellationToken.None));
+    }
+
+    [Fact]
+    public async Task UpdateScheduleAsync_ShouldRejectMismatchedGroupAndExistingMessageReference()
+    {
+        var messenger = CreateMessenger();
+        var message = new PlatformScheduleMessage(
+            new PlatformGroup(PlatformKind.Telegram, "100", "Telegram group", ExternalThreadId: "7"),
+            CreateView(),
+            new PlatformMessageRef(PlatformKind.Telegram, "101", "7", "200"));
+
+        var exception = await Assert.ThrowsAsync<ArgumentException>(
+            () => messenger.UpdateScheduleAsync(message, CancellationToken.None));
+
+        Assert.Equal("message", exception.ParamName);
+        Assert.Contains("Existing schedule message reference must match the schedule group.", exception.Message);
+    }
+
+    private static TelegramPlatformMessenger CreateMessenger() =>
+        new(null!, NullLogger<TelegramPlatformMessenger>.Instance);
+
+    private static SessionBatchViewModel CreateView() =>
+        new("Test batch", []);
+}

tests/GmRelay.Bot.Tests/Infrastructure/Telegram/TelegramTopicIntegrationSmokeTests.cs

@@ -43,18 +43,18 @@ public sealed class TelegramTopicIntegrationSmokeTests
         Assert.Contains("messageThreadId: session.ThreadId", rsvpHandler, StringComparison.Ordinal);
 
         Assert.Contains("int? MessageThreadId", cancelHandler, StringComparison.Ordinal);
-        Assert.Contains("messageThreadId: command.MessageThreadId", cancelHandler, StringComparison.Ordinal);
+        Assert.Contains("TelegramPlatformIds.Group(command.ChatId, command.MessageThreadId)", cancelHandler, StringComparison.Ordinal);
 
         Assert.Contains("int? MessageThreadId", initiateRescheduleHandler, StringComparison.Ordinal);
-        Assert.Contains("messageThreadId: command.MessageThreadId", initiateRescheduleHandler, StringComparison.Ordinal);
+        Assert.Contains("TelegramPlatformIds.Group(command.ChatId, command.MessageThreadId)", initiateRescheduleHandler, StringComparison.Ordinal);
 
         Assert.Contains("int? ThreadId", rescheduleInputHandler, StringComparison.Ordinal);
         Assert.Contains("s.thread_id AS ThreadId", rescheduleInputHandler, StringComparison.Ordinal);
-        Assert.Contains("messageThreadId: proposal.ThreadId", rescheduleInputHandler, StringComparison.Ordinal);
+        Assert.Contains("TelegramPlatformIds.Group(proposal.TelegramChatId, proposal.ThreadId)", rescheduleInputHandler, StringComparison.Ordinal);
 
         Assert.Contains("int? ThreadId", rescheduleDeadlineService, StringComparison.Ordinal);
         Assert.Contains("s.thread_id AS ThreadId", rescheduleDeadlineService, StringComparison.Ordinal);
-        Assert.Contains("messageThreadId: proposal.ThreadId", rescheduleDeadlineService, StringComparison.Ordinal);
+        Assert.Contains("TelegramPlatformIds.Group(proposal.TelegramChatId, proposal.ThreadId)", rescheduleDeadlineService, StringComparison.Ordinal);
     }
 
     private static async Task<string> ReadRepositoryFileAsync(string relativePath)

tests/GmRelay.Bot.Tests/Platform/PlatformContractsTests.cs

@@ -0,0 +1,54 @@
+using GmRelay.Shared.Platform;
+using GmRelay.Shared.Rendering;
+
+namespace GmRelay.Bot.Tests.Platform;
+
+public sealed class PlatformContractsTests
+{
+    [Fact]
+    public void PlatformKind_ShouldDefineTelegramDiscordAndMaxSentinel()
+    {
+        Assert.Equal(0, (int)PlatformKind.Telegram);
+        Assert.Equal(1, (int)PlatformKind.Discord);
+        Assert.Equal(2, (int)PlatformKind.Max);
+    }
+
+    [Fact]
+    public void PlatformContracts_ShouldBeTelegramAssemblyFree()
+    {
+        var contractTypes = new[]
+        {
+            typeof(PlatformUser),
+            typeof(PlatformGroup),
+            typeof(PlatformMessageRef),
+            typeof(PlatformMessageAction),
+            typeof(PlatformScheduleMessage),
+            typeof(PlatformPrivateMessage),
+            typeof(PlatformInteractionReply),
+            typeof(PlatformCalendarFile),
+            typeof(IPlatformMessenger)
+        };
+
+        Assert.All(contractTypes, type =>
+            Assert.DoesNotContain(
+                "Telegram",
+                string.Join(" ", type.Assembly.GetReferencedAssemblies().Select(value => value.Name)),
+                StringComparison.OrdinalIgnoreCase));
+    }
+
+    [Fact]
+    public void PlatformScheduleMessage_ShouldCarrySharedViewModelWithoutPlatformTypes()
+    {
+        var sessionId = Guid.Parse("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa");
+        var view = SessionBatchViewBuilder.Build(
+            "Campaign",
+            [new SessionBatchDto(sessionId, new DateTime(2026, 5, 15, 16, 0, 0, DateTimeKind.Utc), "Planned", 4, "https://example.test/game")],
+            []);
+        var group = new PlatformGroup(PlatformKind.Discord, "guild-1", "Guild", "channel-1", "thread-1");
+
+        var message = new PlatformScheduleMessage(group, view, ExistingMessage: null);
+
+        Assert.Equal(PlatformKind.Discord, message.Group.Platform);
+        Assert.Same(view, message.View);
+    }
+}