refactor：优化目录监控快照

app/chain/storage.py

@@ -110,11 +110,17 @@ class StorageChain(ChainBase):
         """
         return self.run_module("get_parent_item", fileitem=fileitem)
 
-    def snapshot_storage(self, storage: str, path: Path) -> Optional[Dict[str, float]]:
+    def snapshot_storage(self, storage: str, path: Path,
+                         last_snapshot_time: float = None, max_depth: int = 5) -> Optional[Dict[str, Dict]]:
         """
         快照存储
+        :param storage: 存储类型
+        :param path: 路径
+        :param last_snapshot_time: 上次快照时间，用于增量快照
+        :param max_depth: 最大递归深度，避免过深遍历
         """
-        return self.run_module("snapshot_storage", storage=storage, path=path)
+        return self.run_module("snapshot_storage", storage=storage, path=path,
+                               last_snapshot_time=last_snapshot_time, max_depth=max_depth)
 
     def storage_usage(self, storage: str) -> Optional[schemas.StorageUsage]:
         """