added introductory prompt

backend.py

@@ -104,11 +104,10 @@ def handle_query(query_str: str,
             
                   
     else:
-      
         
-        # The index is already built, no need to rebuild it.
-        storage_context = StorageContext.from_defaults(persist_dir=PERSIST_DIR)
-        index = load_index_from_storage(storage_context)
+        index = build_index(matched_path)
+        #storage_context = StorageContext.from_defaults(persist_dir=PERSIST_DIR)
+        #index = load_index_from_storage(storage_context)
         gr.Info("index costruito sulla base dello storage db")    
 
     try: