Feature Request: Support iOS App as Official macOS Photos.app Export Mechanism

Background

Currently, there isn't a good means of exporting photos from a user's macOS "Photos.app" library. You can theoretically find the "originals" folder in the filesystem within each .photoslibrary bundle, but this isn't a good solution since it doesn't preserve edits and metadata.

Since macOS seemingly uses the same (or similar) media/photos/gallery API, the iOS app represents a possible low-effort mechanism for supporting such an export via the "Upload the whole camera roll" setting.

For Nextcloud's privacy-conscious user base, this is a different problem than supporting iCloud export; some of us have large amounts of media imported locally into our libraries, as this used to be the only way to export them from an iOS device while preserving live photos, etc. My personal library, for example, is over half a terabyte.

Proposed Solution

• Allow users to install and use the iOS app in the Mac App Store on M1 Macs.
• Fix the broken login problems on the Catalyst app & support it as an official use case.

Start by reproducing the Catalyst app's login problems and checking whether the iOS app can be installed from the Mac App Store on M1 Macs. Define the supported macOS Photos.app export workflow, including whole-camera-roll uploads, and verify that login and media export work reliably before treating the use case as official.