fix: improve maintenance and synchronize live conversations

backend/app/utils/response_parser.py

@@ -16,7 +16,7 @@ limitations under the License.
 
 import json
 import re
-from typing import Any, Dict, Optional, Type, Union
+from typing import Any, Dict, Type
 from app.core.logger import get_logger
 from app.models.schemas.chat import ChatResponse