Further simplify the AuthenticationViewModel and the public interface of AuthenticationServiceProvider.
Publish currentActiveUser from AuthenticationServiceProvider instead of assuming all callers know to take the first in the list as the active one.
contributes to iOS-319
Also, AppContext, APIService, and AuthenticationServiceProvider are now more obviously singletons.
And AuthenticationServiceProvider can now be asked for the current active user, instead of every caller assuming the first element of a list of users is the active user.
* Add moderation-warning-notification-type (IOS-264)
* Add entity for new AccountWarning (IOS-264)
Details see https://github.com/mastodon/mastodon/pull/30065 for now, as there's no documentation (yet)
* re-add file header (IOS-264)
* Add authorization to instance-calls (IOS-264)
This will improve using the app with `LIMITED_FEDERATION_INSTANCES`
* Add basic cell for account-warnings (IOS-264)
* Show some content for a warning (IOS-264)
* Open strike in browser (IOS-264)
* Add localization (IOS-264)
* Add missing localization (IOS-264)
* Cleanup (IOS-264)
