fix: improve maintenance and synchronize live conversations

backend/app/models/schemas/agent.py

@@ -17,7 +17,6 @@ limitations under the License.
 from datetime import datetime
 from pydantic import BaseModel, Field
 from typing import List, Optional, Dict
-from enum import Enum
 from uuid import UUID
 from app.models.agent import AgentType
 from app.agents.guardrail_policy import GUARDRAIL_PROMPT_MAX