Update src/query_engine.py

src/query_engine.py

@@ -217,7 +217,10 @@ def understand_query(
         result = _parse_qu_result(raw, user_query)
     except Exception:
         # LLM failure: fall back to raw query
-        result = None
+        result = {
+            "search_query": user_query,
+            "sql_query": None,
+        }
 
     return result