feat: Use documentsUI to set the xposedmodule

[Ushie]

Relying on the user to pass in a valid path to the xposed module file is setting them up for a lot of different reasons for failure, now that this feature is used more than ever with forks still requiring this method of installation, it might be the best time to fix this

Instead of using the all files permission and using just a path string, you could instead use a pickFile function that opens a file manager for the user to pick a file from, ideally it would then copy that file to the app's storage to remove the need for the all files permission and to allow the user to delete the downloaded file

P.S.: needs a button to revert to default