feat(web): add private club showcases with membership flow (v3.7.0)

Implements Issue #110: game masters can now publish sessions
exclusively to a club's private showcase, gated behind a
member application and approval flow. Adds a 4-state
publication_mode (None/Catalog/ClubOnly/Both) replacing the
binary is_public, plus a club_memberships table with
Pending/Active/Rejected/Left lifecycle and partial unique
index ensuring a single Active row per (group, player).

Highlights
- V030 migration: club_memberships, publication_mode, drop
  is_public, recreate partial indexes, portfolio_games gains
  publication_mode.
- PublicationMode enum + extensions in GmRelay.Shared.
- ISessionStore gains 12 membership/showcase methods;
  AuthorizedMembershipService owns the membership flow with
  GM-only approve/reject authorization.
- PublicClub / PublicMasterProfile / PublicSession: member-
  aware queries (ClubOnly visible only to Active members).
- New pages: MyClubMemberships (/profile/memberships) and
  ClubApplications (/group/{id}/applications).
- GroupDetails and EditSession switch from a bool toggle to
  a 4-state publication_mode selector.
- NavMenu adds Moji kluby, PublicLayout adds Kluby.

Tests: 4 new test files (PublicationMode, ClubMemberships,
AuthorizedMembershipService, ClubShowcaseSource) + updates
to PublicClubPages, AuthorizedSessionService/Portfolio
service FakeSessionStore, CampaignTemplatesNavigation.
493 tests pass.

Bump version 3.6.0 -> 3.7.0 across Directory.Build.props,
compose.yaml, deploy.yml, NavMenu.razor.

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

tests/GmRelay.Bot.Tests/Web/AuthorizedSessionServiceTests.cs

@@ -839,9 +839,11 @@ public sealed class AuthorizedSessionServiceTests
         public Guid? LastPublicSessionId { get; private set; }
         public Guid? LastPublicSessionGroupId { get; private set; }
         public bool? LastSessionPublicValue { get; private set; }
+        public PublicationMode? LastSessionPublicationMode { get; private set; }
         public Guid? LastPublicBatchId { get; private set; }
         public Guid? LastPublicBatchGroupId { get; private set; }
         public bool? LastBatchPublicValue { get; private set; }
+        public PublicationMode? LastBatchPublicationMode { get; private set; }
         public bool RemovePlayerCalled { get; private set; }
         public Guid? LastRemovedPlayerSessionId { get; private set; }
         public Guid? LastRemovedPlayerGroupId { get; private set; }
@@ -888,45 +890,81 @@ public sealed class AuthorizedSessionServiceTests
             return Task.CompletedTask;
         }
 
-        public Task SetSessionPublicAsync(Guid sessionId, Guid groupId, bool isPublic)
+        public Task SetSessionPublicationModeAsync(Guid sessionId, Guid groupId, PublicationMode mode)
         {
             SetSessionPublicCalled = true;
             LastPublicSessionId = sessionId;
             LastPublicSessionGroupId = groupId;
-            LastSessionPublicValue = isPublic;
+            LastSessionPublicationMode = mode;
 
             if (sessionsById.TryGetValue(sessionId, out var session))
             {
-                sessionsById[sessionId] = session with { IsPublic = isPublic };
+                sessionsById[sessionId] = session with { PublicationMode = mode.ToDatabaseValue() };
             }
 
             return Task.CompletedTask;
         }
 
-        public Task SetBatchPublicAsync(Guid batchId, Guid groupId, bool isPublic)
+        public Task SetBatchPublicationModeAsync(Guid batchId, Guid groupId, PublicationMode mode)
         {
             SetBatchPublicCalled = true;
             LastPublicBatchId = batchId;
             LastPublicBatchGroupId = groupId;
-            LastBatchPublicValue = isPublic;
+            LastBatchPublicationMode = mode;
 
             foreach (var session in sessionsById.Values.Where(session => session.BatchId == batchId && session.GroupId == groupId).ToList())
             {
-                sessionsById[session.Id] = session with { IsPublic = isPublic };
+                sessionsById[session.Id] = session with { PublicationMode = mode.ToDatabaseValue() };
             }
 
             return Task.CompletedTask;
         }
 
-        public Task<WebPublicClub?> GetPublicClubBySlugAsync(string slug) =>
+        public Task<WebPublicClub?> GetPublicClubBySlugAsync(string slug, Guid? viewerPlayerId = null) =>
             Task.FromResult<WebPublicClub?>(null);
 
-        public Task<WebPublicSession?> GetPublicSessionAsync(Guid sessionId) =>
+        public Task<WebPublicSession?> GetPublicSessionAsync(Guid sessionId, Guid? viewerPlayerId = null) =>
             Task.FromResult<WebPublicSession?>(null);
 
         public Task<bool> IsGroupManagerAsync(Guid groupId, long telegramId) =>
             Task.FromResult(IsManager(groupId, telegramId));
 
+        public Task<bool> IsActiveClubMemberAsync(Guid groupId, Guid playerId) =>
+            Task.FromResult(false);
+
+        public Task<Guid?> GetPlayerIdByPlatformIdentityAsync(string platform, string externalUserId) =>
+            Task.FromResult<Guid?>(null);
+
+        public Task<IReadOnlyList<WebClubShowcaseSession>> GetClubShowcaseSessionsAsync(Guid groupId, Guid? viewerPlayerId, int page, int pageSize) =>
+            Task.FromResult<IReadOnlyList<WebClubShowcaseSession>>([]);
+
+        public Task<int> GetPendingApplicationsCountAsync(Guid groupId) =>
+            Task.FromResult(0);
+
+        public Task<List<WebPendingApplication>> GetPendingApplicationsAsync(Guid groupId) =>
+            Task.FromResult(new List<WebPendingApplication>());
+
+        public Task<List<WebMembership>> GetMembershipsForPlayerAsync(Guid playerId) =>
+            Task.FromResult(new List<WebMembership>());
+
+        public Task<Guid> ApplyForMembershipAsync(Guid groupId, Guid playerId, string? message) =>
+            throw new NotImplementedException();
+
+        public Task ApproveMembershipAsync(Guid membershipId, Guid approverPlayerId) =>
+            throw new NotImplementedException();
+
+        public Task RejectMembershipAsync(Guid membershipId, Guid approverPlayerId) =>
+            throw new NotImplementedException();
+
+        public Task LeaveClubMembershipAsync(Guid membershipId, Guid playerId) =>
+            throw new NotImplementedException();
+
+        public Task<Guid?> GetGroupIdForMembershipAsync(Guid membershipId) =>
+            Task.FromResult<Guid?>(null);
+
+        public Task<PublicMasterProfile?> GetPublicMasterProfileBySlugAsync(string slug, Guid? viewerPlayerId = null) =>
+            Task.FromResult<PublicMasterProfile?>(null);
+
         public Task<bool> IsGroupOwnerAsync(Guid groupId, long telegramId) =>
             Task.FromResult(IsOwner(groupId, telegramId));