enh: faster whisper custom model support

backend/open_webui/apps/webui/routers/functions.py

@@ -9,7 +9,7 @@ from open_webui.apps.webui.models.functions import (
     Functions,
 )
 from open_webui.apps.webui.utils import load_function_module_by_id, replace_imports
-from open_webui.config import CACHE_DIR, FUNCTIONS_DIR
+from open_webui.config import CACHE_DIR
 from open_webui.constants import ERROR_MESSAGES
 from fastapi import APIRouter, Depends, HTTPException, Request, status
 from open_webui.utils.utils import get_admin_user, get_verified_user