fix: improve maintenance and synchronize live conversations

backend/tests/agent/test_chat_agent_guardrails.py

@@ -31,7 +31,6 @@ from app.agents.guardrail_policy import (
 )
 from app.models.agent import Agent, AgentType
 from app.models.chat_history import ChatHistory
-from app.models.schemas.chat import ChatResponse
 from app.models.schemas.jira import AgentWithJiraConfig
 from app.utils.guardrail_runtime import BLOCK_REPLY, LEAK_REPLY