How to use the method described in the document on Swift? After using it, I cannot determine whether a file is a dataless file properly. please help me，thanks! I want to use a fileprovider on the macOS platform to implement a feature that only grants allowstagging permission to downloaded files. If it is a dataless file, allowstagging permission will not be given, but the system will automatically drain and clear the content. How to detect this and how to determine if a file is a dataless file