feat(e2e): #148 /newsession scenario from creation to publication

- Add NewSessionScenario that walks the Telegram wizard:
  single game, title, skip description/cover, D&D 5e, 4h, datetime,
  capacity, online format, join link, public visibility, publish, confirm
- Add ClickInlineButtonAsync / ClickInlineButtonByTextAsync to TelegramUserClient
- Add local WizardCallback/Step constants mirroring GmRelay.Shared wizard wire format
- Program.cs now runs full flow: group setup + /newsession + cleanup

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/e2e/runner/TelegramUserClient.cs

@@ -1,4 +1,5 @@
 using System.Collections.Concurrent;
+using System.Text;
 using TL;
 using WTelegram;
 
@@ -69,6 +70,12 @@ public sealed class TelegramUserClient : IDisposable
             .ToList();
     }
 
+    public async Task<Message?> GetLatestBotMessageAsync(ChatGroup group, CancellationToken cancellationToken = default)
+    {
+        var messages = await GetRecentMessagesAsync(group, limit: 20, cancellationToken);
+        return messages.FirstOrDefault(m => m.from_id is not PeerUser userPeer || userPeer.user_id != _client.UserId);
+    }
+
     public async Task<Message?> WaitForBotReplyAsync(
         ChatGroup group,
         string? containsText = null,
@@ -104,6 +111,49 @@ public sealed class TelegramUserClient : IDisposable
         await SendMessageAsync(group, command, cancellationToken);
     }
 
+    public async Task ClickInlineButtonAsync(
+        ChatGroup group,
+        string callbackData,
+        int? messageId = null,
+        CancellationToken cancellationToken = default)
+    {
+        var channel = await ResolveChannelAsync(group.Id, cancellationToken);
+        var targetMessageId = messageId ?? (await GetLatestBotMessageAsync(group, cancellationToken))?.id
+            ?? throw new InvalidOperationException("No bot message found to click.");
+
+        await _client.Messages_GetBotCallbackAnswer(
+            channel,
+            targetMessageId,
+            Encoding.UTF8.GetBytes(callbackData));
+    }
+
+    public async Task ClickInlineButtonByTextAsync(
+        ChatGroup group,
+        string buttonTextContains,
+        int? messageId = null,
+        CancellationToken cancellationToken = default)
+    {
+        var message = messageId.HasValue
+            ? (await GetRecentMessagesAsync(group, limit: 20, cancellationToken)).FirstOrDefault(m => m.id == messageId.Value)
+            : await GetLatestBotMessageAsync(group, cancellationToken);
+
+        if (message is null)
+            throw new InvalidOperationException("No bot message found to click.");
+
+        if (message.reply_markup is not ReplyInlineMarkup markup)
+            throw new InvalidOperationException("Latest bot message has no inline keyboard.");
+
+        var button = markup.rows
+            .SelectMany(r => r.buttons)
+            .OfType<KeyboardButtonCallback>()
+            .FirstOrDefault(b => b.text.Contains(buttonTextContains, StringComparison.OrdinalIgnoreCase));
+
+        if (button is null)
+            throw new InvalidOperationException($"No inline button matching '{buttonTextContains}' found.");
+
+        await ClickInlineButtonAsync(group, Encoding.UTF8.GetString(button.data), message.id, cancellationToken);
+    }
+
     public void Dispose()
     {
         _client.Dispose();