[fix] race condition

usecase/interface.py

@@ -28,6 +28,21 @@ class SandboxSessionRepository(Protocol):
     def delete(self, session_id: str) -> None: ...
 
 
+class LockContext(Protocol):
+    def __enter__(self) -> None: ...
+
+    def __exit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc: BaseException | None,
+        traceback: TracebackType | None,
+    ) -> bool | None: ...
+
+
+class SandboxLifecycleLocker(Protocol):
+    def lock(self, chat_id: str) -> LockContext: ...
+
+
 class SandboxRuntime(Protocol):
     def create(
         self,