fix: improve maintenance and synchronize live conversations

backend/tests/services/test_app_first_routing.py

@@ -31,7 +31,7 @@ from app.channels.app_hooks import (
 from app.channels.base import InboundMessage
 from app.models.channels import ChannelConversation
 from app.models.chat_history import ChatHistory
-from app.models.session_to_agent import SessionToAgent, SessionStatus
+from app.models.session_to_agent import SessionToAgent
 from app.repositories.channels import AgentChannelConfigRepository, ChannelAccountRepository
 from app.repositories.chat import ChatRepository
 from app.services import agent_rooms, app_first_routing, channel_chat