feat: freeze usage update in Searcher (#466)

* feat: tmp-close usage update, maybe reopen it later

* test: withdraw update usage test

Author: CaralHsi

src/memos/memories/textual/tree_text_memory/retrieve/searcher.py

@@ -1,8 +1,5 @@
-import json
 import traceback
 
-from datetime import datetime
-
 from memos.context.context import ContextThreadPoolExecutor
 from memos.embedders.factory import OllamaEmbedder
 from memos.graph_dbs.factory import Neo4jGraphDB
@@ -508,7 +505,7 @@ def _sort_and_trim(self, results, top_k):
 
     @timed
     def _update_usage_history(self, items, info, user_name: str | None = None):
-        """Update usage history in graph DB"""
+        """Update usage history in graph DB
         now_time = datetime.now().isoformat()
         info_copy = dict(info or {})
         info_copy.pop("chat_history", None)
@@ -532,6 +529,7 @@ def _update_usage_history(self, items, info, user_name: str | None = None):
             self._usage_executor.submit(
                 self._update_usage_history_worker, payload, usage_record, user_name
             )
+        """
 
     def _update_usage_history_worker(
         self, payload, usage_record: str, user_name: str | None = None

tests/memories/textual/test_tree_searcher.py

@@ -69,13 +69,6 @@ def test_searcher_fast_path(mock_searcher):
     assert len(result) <= 2
     assert all(isinstance(item, TextualMemoryItem) for item in result)
 
-    # Should update usage and call update_node
-    for item in result:
-        assert len(item.metadata.usage) > 0
-        mock_searcher.graph_store.update_node.assert_any_call(
-            item.id, {"usage": item.metadata.usage}, user_name=None
-        )
-
 
 def test_searcher_fine_mode_triggers_reasoner(mock_searcher):
     parsed_goal = MagicMock()