导入方式修改

backend/app/backend.py

@@ -3,8 +3,13 @@ FastAPI 后端 - 支持动态模型切换，使用 PostgreSQL 持久化记忆
 采用依赖注入模式，优雅管理资源生命周期
 """
 
+import warnings
+# 抑制 WebSocket 弃用警告（websockets 库升级导致，uvicorn 尚未跟进）
+warnings.filterwarnings("ignore", category=DeprecationWarning, module="websockets")
+warnings.filterwarnings("ignore", category=DeprecationWarning, module="uvicorn.protocols.websockets")
+
 import os
-from app.config import DB_URI, BACKEND_PORT
+from ..config import DB_URI, BACKEND_PORT
 import uuid
 import json
 from contextlib import asynccontextmanager
@@ -15,26 +20,26 @@ from fastapi.middleware.cors import CORSMiddleware
 from fastapi.responses import StreamingResponse
 from pydantic import BaseModel
 from langgraph.checkpoint.postgres.aio import AsyncPostgresSaver
-from .agent.agent_service import AIAgentService
+from .agent.agent_service import AIAgentService, create_serde
 from .agent.history import ThreadHistoryService
-from app.core.human_review import (
+from ..core.human_review import (
     ReviewManager,
     InMemoryReviewStore,
     ReviewStatus,
     HumanReview
 )
-from app.subgraphs.contact.api_client import ContactAPIClient
-from app.subgraphs.dictionary.api_client import DictionaryAPIClient
-from app.subgraphs.news_analysis.api_client import NewsAPIClient
+from ..subgraphs.contact.api_client import ContactAPIClient
+from ..subgraphs.dictionary.api_client import DictionaryAPIClient
+from ..subgraphs.news_analysis.api_client import NewsAPIClient
 from .db.init_db import init_subgraph_tables
 from .db.models import ContactRepository, DictionaryRepository, NewsRepository
-from app.logger import info, error
+from ..logger import info, error
 
 @asynccontextmanager
 async def lifespan(app: FastAPI):
     """应用生命周期管理：创建并注入全局服务"""
     # 1. 创建数据库连接池并初始化表（仅 checkpointer）
-    async with AsyncPostgresSaver.from_conn_string(DB_URI) as checkpointer:
+    async with AsyncPostgresSaver.from_conn_string(DB_URI, serde=create_serde()) as checkpointer:
         await checkpointer.setup()
         
         # 1.5 初始化子图表