refactor: standardize runtime annotation types across multiple files

backend/app/schemas/board_group_heartbeat.py

@@ -3,10 +3,12 @@
 from __future__ import annotations
 
 from typing import Any
-from uuid import UUID  # noqa: TCH003
+from uuid import UUID
 
 from sqlmodel import SQLModel
 
+RUNTIME_ANNOTATION_TYPES = (UUID,)
+
 
 class BoardGroupHeartbeatApply(SQLModel):
     """Request payload for heartbeat policy updates."""