Ignore chat history in vector search

lightrag/operate.py

@@ -1199,16 +1199,11 @@ async def mix_kg_vector_query(
             return None
 
     async def get_vector_context():
-        # Consider conversation history in vector search
-        augmented_query = query
-        if history_context:
-            augmented_query = f"{history_context}\n{query}"
-
         try:
             # Reduce top_k for vector search in hybrid mode since we have structured information from KG
             mix_topk = min(10, query_param.top_k)
             results = await chunks_vdb.query(
-                augmented_query, top_k=mix_topk, ids=query_param.ids
+                query, top_k=mix_topk, ids=query_param.ids
             )
             if not results:
                 return None