Simplify AI memory pipeline

api/app/features/memory/retriever.py

@@ -11,7 +11,7 @@ logger = get_logger(__name__)
 
 
 class HybridRetriever:
-    """向量 chunk 检索 + facts/timeline/summaries/stories。"""
+    """向量 chunk 检索 + facts/summaries/stories。"""
 
     def __init__(
         self,
@@ -25,7 +25,7 @@ class HybridRetriever:
     async def retrieve(self, user_id: str, query: str, *, top_k: int = 10) -> dict:
         """
         Return evidence bundle:
-        {relevant_chunks, relevant_summaries, relevant_facts, timeline_hints, relevant_stories}
+        {relevant_chunks, relevant_summaries, relevant_facts, relevant_stories}
         """
         if not query.strip():
             return await retrieve_evidence_bundle_async(