fixed bot and server connectivity issues

backend/src/shared/di_container.py

@@ -39,13 +39,9 @@ from src.application.use_cases.rag_use_cases import RAGUseCases
 
 class DatabaseProvider(Provider):
     @provide(scope=Scope.REQUEST)
-    @asynccontextmanager
     async def get_db(self) -> AsyncSession:
-        async with AsyncSessionLocal() as session:
-            try:
-                yield session
-            finally:
-                await session.close()
+        session = AsyncSessionLocal()
+        return session
 
 
 class RepositoryProvider(Provider):