Implement AltStore Issue #927

[nythepegasus]

AltStore Issue for reference.

It seems like a lot of QOL enhancements we could use in SideServer.

Could also ask @rrroyal to help out.

[lonkelle]

@nythepegasus I just asked @rrroyal about this on Twitter and they're willing to separate the two PRs but honestly, I think we should grab the PR in it's entirety. (reference: https://twitter.com/destroystokyo/status/1603645974001471488).

Both the Progress View and especially the keychain feature would be godsends for testing given we reinstall all the time.

VIDEO_M_ID_1480354521180254209_20221216003410.mp4

[lonkelle]

I really wanted to cherry pick this before SideServer for macOS's release on the 18th. But this will have to be a 1.1 feature because 1.0 is already too hectic. It's just so much nicer than notifications and those checkmarks feel so good. Ahhh. 😆