feat：物料存入数据库

app/services/persistence.py

@@ -2,6 +2,7 @@
 
 from collections.abc import Awaitable, Callable
 from dataclasses import dataclass
+from typing import Any
 
 from langgraph.checkpoint.base import BaseCheckpointSaver
 from loguru import logger
@@ -16,6 +17,8 @@ class Persistence:
     # 为空时由图使用默认的内存检查点
     checkpointer: BaseCheckpointSaver | None
     close: Callable[[], Awaitable[None]]
+    # 启用 MongoDB 时的数据库，供物料等其他集合复用同一连接
+    db: Any = None
 
 
 async def _close_nothing() -> None:
@@ -67,4 +70,4 @@ async def open_persistence() -> Persistence:
         raise
 
     logger.info("已启用 MongoDB 持久化，库名 {}", settings.mongodb_db)
-    return Persistence(store, checkpointer, close)
+    return Persistence(store, checkpointer, close, async_client[settings.mongodb_db])