Fix mypy type annotations for _to_thread_with_lock

Add TypeVar to preserve return types through the _to_thread_with_lock
wrapper method. This fixes mypy errors about returning Any from functions
with concrete return type declarations.

- Import Callable and TypeVar from typing
- Add generic TypeVar T
- Annotate _to_thread_with_lock with proper generic types
- Annotate wrapped() inner function return type

Author: gn00295120

src/agents/memory/sqlite_session.py

@@ -5,10 +5,13 @@
 import sqlite3
 import threading
 from pathlib import Path
+from typing import Callable, TypeVar
 
 from ..items import TResponseInputItem
 from .session import SessionABC
 
+T = TypeVar("T")
+
 
 class SQLiteSession(SessionABC):
     """SQLite-based implementation of session storage.
@@ -54,7 +57,7 @@ def _get_connection(self) -> sqlite3.Connection:
         """Get a database connection."""
         return self._shared_connection
 
-    async def _to_thread_with_lock(self, func, *args, **kwargs):
+    async def _to_thread_with_lock(self, func: Callable[..., T], *args, **kwargs) -> T:
         """Execute a function in a thread pool with lock protection.
 
         This ensures thread-safe access to the shared database connection
@@ -70,7 +73,7 @@ async def _to_thread_with_lock(self, func, *args, **kwargs):
             The result of the function execution
         """
 
-        def wrapped():
+        def wrapped() -> T:
             with self._lock:
                 return func(*args, **kwargs)