fix: sub-room id sequence, restore sync, presence index TTL, permission races

From the local CodeRabbit review:
- Scene ids: the repair and room clone assigned max + 1, which never
  advanced the Postgres identity sequence (live: sequence 3412, max id 3466),
  so the next add / clone sub-room would collide on the primary key. The
  repair now moves the sequence past the highest id at startup, and both
  let the database assign ids.
- Room-level restores (datahistory/restore and the admin restore) now also
  restore the entry sub-room, whose blob room details serve first.
- TouchRoom refreshes the room's presence index too, so players kept alive
  only by heartbeats no longer drop out of the instance browser after 20 min.
- Sub-room permission saves match cells exactly (as the unique index does)
  and retry when a concurrent editor inserted the same new cell.

DorkNet.Server.Tests/SubRoomsAndInstances2023Tests.cs

@@ -118,6 +118,35 @@ public sealed class SubRoomsAndInstances2023Tests : IClassFixture<DorkNetServerF
         Assert.Equal((0, 0), await service.RepairRoomScenesAsync());
     }
 
+    [Fact]
+    public async Task Room_level_restore_also_restores_the_entry_sub_room()
+    {
+        var owner = await PlayerAsync();
+        var roomId = await SeedRoomAsync(owner.PlayerId, accessibility: 0, scenes: new[] { "Home", "Back" });
+        await using (var scope = _factory.Services.CreateAsyncScope())
+        {
+            var db = scope.ServiceProvider.GetRequiredService<DorkNetDbContext>();
+            await db.RoomScenes.Where(s => s.RoomId == roomId)
+                .ExecuteUpdateAsync(s => s.SetProperty(x => x.DataBlobName, "blob-old"));
+            db.RoomDataBlobs.Add(new RoomDataBlobEntity { RoomId = roomId, BlobName = "blob-new", UploadedByPlayerId = owner.PlayerId });
+            await db.SaveChangesAsync();
+        }
+
+        using var api = Client("api", owner);
+        using var response = await api.PostAsync("/api/rooms/v1/restore", new FormUrlEncodedContent(new Dictionary<string, string>
+        {
+            ["roomId"] = roomId.ToString(), ["blobName"] = "blob-new",
+        }));
+        Assert.True(response.IsSuccessStatusCode, await response.Content.ReadAsStringAsync());
+
+        await using var check = _factory.Services.CreateAsyncScope();
+        var checkDb = check.ServiceProvider.GetRequiredService<DorkNetDbContext>();
+        var blobs = await checkDb.RoomScenes.AsNoTracking().Where(s => s.RoomId == roomId)
+            .OrderBy(s => s.OrderIndex).Select(s => s.DataBlobName).ToListAsync();
+        // The entry sub-room follows the restore; other sub-rooms keep theirs.
+        Assert.Equal(new[] { "blob-new", "blob-old" }, blobs);
+    }
+
     [Fact]
     public async Task Startup_repair_restores_a_missing_entry_sub_room_next_to_others()
     {

DorkNet.Server/Controllers/API/Rooms/V2/RoomsController.cs

@@ -1406,6 +1406,7 @@ public class RoomsController(
             .ExecuteUpdateAsync(s => s
                 .SetProperty(r => r.CurrentDataBlobName, blob.BlobName)
                 .SetProperty(r => r.UpdatedAt, DateTime.UtcNow));
+        if (!room.IsDormRoom) await SyncEntrySceneBlobAsync(room.Id, blob.BlobName);
         await db.SaveChangesAsync();
 
         // Push the same SubscriptionUpdateRoom the save flow sends so
@@ -1479,10 +1480,27 @@ public class RoomsController(
             .ExecuteUpdateAsync(s => s
                 .SetProperty(r => r.CurrentDataBlobName, blob.BlobName)
                 .SetProperty(r => r.UpdatedAt, DateTime.UtcNow));
+        if (!room.IsDormRoom) await SyncEntrySceneBlobAsync(roomId, blob.BlobName);
         await db.SaveChangesAsync();
         return Ok(new { restored = blob.BlobName });
     }
 
+    /// <summary>A room-level restore also restores the entry sub-room
+    /// (OrderIndex 0): room details serve the entry scene's own blob ahead
+    /// of the room's, so updating only <c>Rooms.CurrentDataBlobName</c>
+    /// would leave the old version in place. The per-sub-room restore keeps
+    /// the two in step the other way round. Dorms keep their blob per
+    /// player (DormState) instead.</summary>
+    private Task SyncEntrySceneBlobAsync(long roomId, string blobName)
+    {
+        var now = DateTime.UtcNow;
+        return db.RoomScenes
+            .Where(s => s.RoomId == roomId && s.OrderIndex == 0)
+            .ExecuteUpdateAsync(s => s
+                .SetProperty(x => x.DataBlobName, blobName)
+                .SetProperty(x => x.DataModifiedAt, now));
+    }
+
     /// <summary>GET <c>api/rooms/v{1,2}/personaldetails/{roomId}</c> —
     /// per-caller bookmark/cheer flags for one room. Wire shape verified
     /// against <c>RecNet.PersonalRoomDetails.Deserialize</c>
@@ -3829,35 +3847,51 @@ public class RoomsController(
         var scene = await GetOrCreateSceneForMutationAsync(room, subRoomId);
         if (scene is null) return NotFound();
 
-        var existing = await db.RoomRolePermissions
-            .Where(p => p.RoomId == roomId && p.SubRoomId == subRoomId)
-            .ToListAsync();
         var now = DateTime.UtcNow;
-        foreach (var cell in cells)
-        {
-            var row = existing.FirstOrDefault(p =>
-                p.Role == cell.Role
-                && string.Equals(p.Permission, cell.Permission, StringComparison.OrdinalIgnoreCase));
-            if (row is null)
-            {
-                row = new RoomRolePermissionEntity
-                {
-                    RoomId = roomId,
-                    SubRoomId = subRoomId,
-                    Role = cell.Role,
-                    Permission = cell.Permission,
-                };
-                db.RoomRolePermissions.Add(row);
-                existing.Add(row);
-            }
-            row.Type = cell.Type;
-            row.Override = cell.Override;
-            row.Value = cell.Value;
-            row.UpdatedByPlayerId = pid;
-            row.UpdatedAt = now;
-        }
         scene.DataModifiedAt = now;
-        await db.SaveChangesAsync();
+        for (var attempt = 1; ; attempt++)
+        {
+            var existing = await db.RoomRolePermissions
+                .Where(p => p.RoomId == roomId && p.SubRoomId == subRoomId)
+                .ToListAsync();
+            foreach (var cell in cells)
+            {
+                // Exact match, like the unique index on
+                // (RoomId, SubRoomId, Role, Permission).
+                var row = existing.FirstOrDefault(p =>
+                    p.Role == cell.Role && string.Equals(p.Permission, cell.Permission, StringComparison.Ordinal));
+                if (row is null)
+                {
+                    row = new RoomRolePermissionEntity
+                    {
+                        RoomId = roomId,
+                        SubRoomId = subRoomId,
+                        Role = cell.Role,
+                        Permission = cell.Permission,
+                    };
+                    db.RoomRolePermissions.Add(row);
+                    existing.Add(row);
+                }
+                row.Type = cell.Type;
+                row.Override = cell.Override;
+                row.Value = cell.Value;
+                row.UpdatedByPlayerId = pid;
+                row.UpdatedAt = now;
+            }
+            try
+            {
+                await db.SaveChangesAsync();
+                break;
+            }
+            catch (DbUpdateException) when (attempt < 3)
+            {
+                // Another editor inserted the same new cell between our read
+                // and our insert (unique index). Forget our pending rows and
+                // apply the cells again, now as updates of theirs.
+                foreach (var entry in db.ChangeTracker.Entries<RoomRolePermissionEntity>().ToList())
+                    entry.State = EntityState.Detached;
+            }
+        }
 
         logger.LogInformation(
             "[subroom-permissions] room={Room} sub={Sub} by={By} cells={Count}",

DorkNet.Server/Services/PlayerPresenceService.cs

@@ -141,7 +141,19 @@ public class PlayerPresenceService
         {
             try
             {
-                mux.GetDatabase().KeyExpire(Key(playerId), PresenceTtl);
+                var db = mux.GetDatabase();
+                db.KeyExpire(Key(playerId), PresenceTtl);
+                // Keep the room's membership index alive as long as its
+                // members are: a player refreshed only through here would
+                // otherwise outlive the set (SetRoom's 2 × TTL) and drop out
+                // of the instance browser and room pushes.
+                var json = db.StringGet(Key(playerId));
+                if (json.HasValue &&
+                    JsonSerializer.Deserialize<RoomInstanceDto>(json.ToString(), JsonOpts) is { RoomId: > 0 } room)
+                {
+                    db.SetAdd(RoomIndexKey(room.RoomId), playerId);
+                    db.KeyExpire(RoomIndexKey(room.RoomId), PresenceTtl + PresenceTtl);
+                }
             }
             catch (Exception ex)
             {

DorkNet.Server/Services/RoomPermissionMatrix.cs

@@ -60,7 +60,7 @@ public static class RoomPermissionMatrix
             var cell = new Cell(row.Permission, row.Role, row.Override, row.Type, row.Value);
             var at = cells.FindIndex(c =>
                 c.Role == row.Role
-                && string.Equals(c.Permission, row.Permission, StringComparison.OrdinalIgnoreCase));
+                && string.Equals(c.Permission, row.Permission, StringComparison.Ordinal));
             if (at >= 0) cells[at] = cell;
             else cells.Add(cell);
         }

DorkNet.Server/Services/RoomService.cs

@@ -570,6 +570,22 @@ public class RoomService(DorkNetDbContext db)
         DataModifiedAt = DateTime.UtcNow,
     };
 
+    /// <summary>Postgres only: moves the RoomScenes id sequence past the
+    /// highest existing id. Rows written with explicit ids (seeds, older
+    /// builds of the clone and repair code) leave it behind, and the next
+    /// insert that relies on it (add / clone sub-room) then collides on the
+    /// primary key. A no-op on SQLite, which assigns max + 1 itself.</summary>
+    public async Task SyncRoomSceneIdSequenceAsync()
+    {
+        if (!db.Database.IsNpgsql()) return;
+        await db.Database.ExecuteSqlRawAsync(
+            """
+            SELECT setval(pg_get_serial_sequence('"RoomScenes"', 'Id'),
+                          GREATEST(COALESCE((SELECT MAX("Id") FROM "RoomScenes"), 0), 1),
+                          EXISTS (SELECT 1 FROM "RoomScenes"));
+            """);
+    }
+
     /// <summary>Startup self-heal for sub-rooms (idempotent).
     ///
     /// <para>Every non-dorm room must own at least one real RoomScenes row,
@@ -583,12 +599,12 @@ public class RoomService(DorkNetDbContext db)
     /// are left alone: their details are shaped per player and their single
     /// scene is synthesised on purpose.</para>
     ///
-    /// <para>Scene ids are assigned explicitly (max + 1) for the same reason
+    /// <para>It first moves the Postgres id sequence of RoomScenes past the
-    /// the clone handler does: seeded rows were inserted with manual ids
+    /// highest id (<see cref="SyncRoomSceneIdSequenceAsync"/>), then lets the
-    /// without advancing the Postgres identity sequence. Every service that
+    /// database assign ids like every other scene insert. Every service that
     /// runs the database bootstrap calls this at startup, so on Postgres the
-    /// whole repair holds the bootstrap's advisory lock: replicas booting
+    /// whole repair holds the bootstrap's advisory lock and replicas booting
-    /// together take turns instead of handing out the same ids.</para>
+    /// together take turns.</para>
     /// Returns (rooms given an entry scene, scenes renamed).</summary>
     public async Task<(int ScenesAdded, int ScenesRenamed)> RepairRoomScenesAsync()
     {
@@ -598,16 +614,13 @@ public class RoomService(DorkNetDbContext db)
 
         // The entry sub-room is OrderIndex 0 (its blob is the room's own front
         // door), so a room missing it is repaired even when it has others.
+        await SyncRoomSceneIdSequenceAsync();
+
         var roomsWithoutEntry = await db.Rooms
             .Where(r => !r.IsDormRoom && !db.RoomScenes.Any(s => s.RoomId == r.Id && s.OrderIndex == 0))
             .ToListAsync();
-        var nextSceneId = await db.RoomScenes.MaxAsync(s => (long?)s.Id) ?? 0L;
         foreach (var room in roomsWithoutEntry)
-        {
+            db.RoomScenes.Add(NewHomeScene(room));
-            var scene = NewHomeScene(room);
-            scene.Id = ++nextSceneId;
-            db.RoomScenes.Add(scene);
-        }
 
         var unnamed = await db.RoomScenes
             .Where(s => s.Name == null || s.Name.Trim() == string.Empty)
@@ -1144,9 +1157,7 @@ public class RoomService(DorkNetDbContext db)
 
         db.Rooms.Add(clone);
         // Every room owns a real entry sub-room (see RepairRoomScenesAsync).
-        var home = NewHomeScene(clone);
+        db.RoomScenes.Add(NewHomeScene(clone));
-        home.Id = (await db.RoomScenes.MaxAsync(s => (long?)s.Id) ?? 0L) + 1;
-        db.RoomScenes.Add(home);
         await db.SaveChangesAsync();
         return new CloneResult(0 /* Success */, clone);
     }