Xcode Cloud Docs (next-dev)

[Camji55]

This change allows building and distributing with Xcode Cloud which I have been doing on my personal branch for some time now. The intent is that existing workflows for browser builds with GitHub Actions and all Continuous Integration actions should still work as-is since Fastlane should override these code-signing settings. This will need some testing before it gets adopted but having the option to build and deploy within Xcode itself would be beneficial for users who'd like to take advantage of it especially if other options still remain available.

I'm also working on a write up on how to setup Xcode Cloud as an alternative to GitHub Actions for browser builds.

Please let me know what I can do to help verify all Fastlane and GitHub Actions remain working!

next-dev clone of #2347

[ps2]

Thanks for writing this up, @Camji55! I checked the doc against the current project settings, and it's close. A few things to fix before merging:

1. App group name. Step 3 says the app group is group.com.<TEAMID>.loopkit.LoopGroup. The project builds it as group.$(MAIN_APP_BUNDLE_IDENTIFIER)Group, so it's actually group.com.<TEAMID>.loopkitGroup.
2. Clone branch. Step 1 clones --branch=dev. Most people should build main (the release branch); dev/next-dev could be mentioned as an option for testers.
3. PR description. It still describes enabling automatic code signing, but the diff is now docs only. Signing is already automatic with "Apple Development" on both dev (via the LOOP_CODE_SIGN_* variables) and next-dev (hardcoded), so the description should just say it adds the Xcode Cloud guide.
4. Formatting. In Step 4, "TestFlight (Internal Testing Only)" ended up on a broken nested bullet under Actions; it reads better inline ("an Archive action with distribution preparation set to TestFlight (Internal Testing Only)"). There's also a missing blank line before the --- after the "Keeping current" list.

Checked and correct: the bundle ID derives from DEVELOPMENT_TEAM, LoopConfigOverride.xcconfig ends with the commented LOOP_DEVELOPMENT_TEAM line, LoopWorkspace is a shared scheme (and the right one, since Loop builds without the plugins), the listed package dependencies match Package.resolved, and the 25 compute hours / 90-day TestFlight expiry are right.

Not blocking, but worth considering:

• The central claim is that Xcode Cloud supplies the team even though LOOP_DEVELOPMENT_TEAM is empty in the repo, so nothing needs committing. That matches your experience, but it would be good to confirm once from a fresh fork.
• Loop/Documentation/ only holds images today, so this may be hard to find. A link from LoopDocs or the LoopWorkspace README would help people discover it.
• This doc is identical to #2347. If next-dev picks up dev changes when they're synced, merging just one would avoid two copies drifting apart.