Clarify the use of contexts:
- **Production** (.shared)
- **Previews** (.mock → .forPreviews)
- ONLY use it in UILibrary for, well, previews
- This context has dumb profiles with UUIDs as names
- Registry is fake
- **UI Tests** (.forUITesting)
- Add new context for UI testing
- Selected based on command line arguments
- This context has mock data tuned for decent screenshots
- Registry is real
Share the same InAppProcessor in .shared and .forTesting contexts
because the app behavior was inconsistent regarding e.g. in-app
purchases.
2a467e0c7e