feat:修复投顾agent功能

nl2sql/retrieval.py

@@ -1,6 +1,7 @@
 """NL2SQL 元数据召回与授权过滤。"""
 from __future__ import annotations
 
+import asyncio
 from collections.abc import Awaitable, Callable, Iterable
 from typing import Any
 
@@ -70,15 +71,21 @@ async def retrieve_metadata(
         "is_valid",
         "is_deprecated",
     ]
-    results: list[dict[str, Any]] = []
-    for chunk_type in ("table_meta", "field_meta"):
-        hits = await milvus_client.search(
+    async def search_chunk(chunk_type: str):
+        return await milvus_client.search(
             collection_name=NL2SQL_COLLECTION,
             data=[vector],
             limit=top_k,
             filter=f'chunk_type == "{chunk_type}" and is_valid == true',
             output_fields=output_fields,
         )
+
+    table_hits, field_hits = await asyncio.gather(
+        search_chunk("table_meta"),
+        search_chunk("field_meta"),
+    )
+    results: list[dict[str, Any]] = []
+    for hits in (table_hits, field_hits):
         for hit in _flatten_hits(hits):
             entity = hit.get("entity") or hit
             if not entity.get("is_valid", True) or entity.get("is_deprecated", False):