feat: async file upload

backend/open_webui/routers/images.py

@@ -469,7 +469,9 @@ def upload_image(request, image_data, content_type, metadata, user):
             "content-type": content_type,
         },
     )
-    file_item = upload_file(request, file, metadata=metadata, internal=True, user=user)
+    file_item = upload_file(
+        request, file=file, metadata=metadata, process=False, user=user
+    )
     url = request.app.url_path_for("get_file_content_by_id", id=file_item.id)
     return url