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/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)
             {