fix: update search API to query_points for qdrant-client 1.9+

vector_store.py

@@ -129,15 +129,15 @@ class QdrantVectorStore:
                 )]
             )
         
-        results = self.client.search(
+        results = self.client.query_points(
             collection_name=config.QDRANT_COLLECTION,
-            query_vector=query_embedding.tolist(),
+            query=query_embedding.tolist(),
             query_filter=filter_condition,
             limit=top_k
         )
         
         search_results = []
-        for i, hit in enumerate(results):
+        for i, hit in enumerate(results.points):
             chunk = DocumentChunk(
                 chunk_id=hit.payload["chunk_id"],
                 paper_id=hit.payload["paper_id"],