fix(data): serialize portfolio mutations before rows

src/GmRelay.Bot/Migrations/V029__add_completed_game_portfolios_and_reviews.sql

@@ -52,6 +52,46 @@ CREATE TABLE portfolio_game_masters (
 CREATE INDEX ix_portfolio_game_masters_player
     ON portfolio_game_masters (player_id, portfolio_game_id);
 
+CREATE FUNCTION lock_portfolio_publication_mutation()
+RETURNS TRIGGER
+LANGUAGE plpgsql
+AS $$
+BEGIN
+    PERFORM pg_advisory_xact_lock(20260530, 108);
+    RETURN NULL;
+END;
+$$;
+
+CREATE TRIGGER trg_portfolio_games_lock_publication_mutation
+BEFORE INSERT OR DELETE OR UPDATE OF is_public ON portfolio_games
+FOR EACH STATEMENT
+EXECUTE FUNCTION lock_portfolio_publication_mutation();
+
+CREATE TRIGGER trg_portfolio_game_sessions_lock_publication_mutation
+BEFORE INSERT OR DELETE OR UPDATE ON portfolio_game_sessions
+FOR EACH STATEMENT
+EXECUTE FUNCTION lock_portfolio_publication_mutation();
+
+CREATE TRIGGER trg_portfolio_game_masters_lock_publication_mutation
+BEFORE INSERT OR DELETE OR UPDATE ON portfolio_game_masters
+FOR EACH STATEMENT
+EXECUTE FUNCTION lock_portfolio_publication_mutation();
+
+CREATE TRIGGER trg_sessions_lock_portfolio_publication_mutation
+BEFORE DELETE OR UPDATE OF scheduled_at ON sessions
+FOR EACH STATEMENT
+EXECUTE FUNCTION lock_portfolio_publication_mutation();
+
+CREATE TRIGGER trg_game_groups_lock_portfolio_publication_mutation_before_delete
+BEFORE DELETE ON game_groups
+FOR EACH STATEMENT
+EXECUTE FUNCTION lock_portfolio_publication_mutation();
+
+CREATE TRIGGER trg_players_lock_portfolio_publication_mutation_before_delete
+BEFORE DELETE ON players
+FOR EACH STATEMENT
+EXECUTE FUNCTION lock_portfolio_publication_mutation();
+
 CREATE FUNCTION validate_public_portfolio_game_required_links()
 RETURNS TRIGGER
 LANGUAGE plpgsql

src/GmRelay.DiscordBot/Features/Sessions/DiscordDeleteSessionHandler.cs

@@ -45,6 +45,9 @@ public sealed class DiscordDeleteSessionHandler(
         }
 
         await using var transaction = await connection.BeginTransactionAsync(cancellationToken);
+        await connection.ExecuteAsync(
+            "SELECT pg_advisory_xact_lock(20260530, 108)",
+            transaction: transaction);
         _ = await connection.QuerySingleOrDefaultAsync<Guid?>(
             """
             SELECT s.id

src/GmRelay.Shared/Features/Sessions/ListSessions/DeleteSessionHandler.cs

@@ -31,7 +31,12 @@ public sealed class DeleteSessionHandler(
         await using var connection = await dataSource.OpenConnectionAsync(ct);
         await using var transaction = await connection.BeginTransactionAsync(ct);
 
-        // 1. Lock the session before any linked portfolio card and verify group manager.
+        // 1. Use the database mutation order before locking the session or linked portfolio cards.
+        await connection.ExecuteAsync(
+            "SELECT pg_advisory_xact_lock(20260530, 108)",
+            transaction: transaction);
+
+        // 2. Lock the session before any linked portfolio card and verify group manager.
         var session = await connection.QuerySingleOrDefaultAsync<DeleteSessionInfoDto>(
             """
             SELECT s.title AS Title,
@@ -63,7 +68,7 @@ public sealed class DeleteSessionHandler(
             return new DeleteSessionResult(false, "Только owner или co-GM может удалять сессию.", null, null, null, false, 0);
         }
 
-        // 2. Unpublish a linked portfolio card before its required session link cascades away.
+        // 3. Unpublish a linked portfolio card before its required session link cascades away.
         await connection.ExecuteAsync(
             """
             UPDATE portfolio_games pg
@@ -77,7 +82,7 @@ public sealed class DeleteSessionHandler(
             new { command.SessionId },
             transaction);
 
-        // 3. Delete session
+        // 4. Delete session
         await connection.ExecuteAsync("DELETE FROM sessions WHERE id = @Id", new { Id = command.SessionId }, transaction);
 
         var remainingInTopic = session.ThreadId.HasValue