fix(aider): remove dead get_aider_event_repository factory (resource leak)

get_db_context import unused after removing broken factory function.
Worker manages its own session via get_session_factory(). 2026-04-20 @ Asia/Taipei

apps/api/src/repositories/aider_event_repository.py

@@ -13,8 +13,6 @@ import structlog
 from sqlalchemy import text
 from sqlalchemy.ext.asyncio import AsyncSession
 
-from src.db.base import get_db_context
-
 logger = structlog.get_logger(__name__)
 
 
@@ -132,20 +130,3 @@ def _json(obj: Any) -> str:
     """序列化 Python object 為 JSON string (JSONB 注入用)"""
     return json.dumps(obj, ensure_ascii=False, default=str)
 
-
-# =============================================================================
-# Singleton Factory
-# =============================================================================
-
-_aider_event_repo: AiderEventRepository | None = None
-
-
-async def get_aider_event_repository() -> AiderEventRepository:
-    """取得 AiderEventRepository 實例 (async factory)
-
-    用法：
-        async with get_db_context() as db:
-            repo = AiderEventRepository(db)
-            event_id = await repo.insert(...)
-    """
-    return AiderEventRepository(await get_db_context().__aenter__())