refactor: 推进后端分层架构治理

app/agent/callback/__init__.py

@@ -8,7 +8,7 @@ from fastapi.concurrency import run_in_threadpool
 from app.agent.policy import sanitize_for_host
 from app.chain import ChainBase
 from app.runtime.log import logger
-from app.schemas import Message
+from app.schemas.message import Message
 from app.schemas.message import (
     MessageResponse,
     ChannelCapabilityManager,