* vector-im/element-x-ios/issues/31 - Session verification unit and UI tests
* Fix ImageAnonymizer tests when running on Apple Silicon
* Rename SessionVerification to SessionVerificationScreen
- updated the authentication coordinator to use async await
- replaced the UserSession with a ClientProxy (similar to the RoomProxy)
- renamed `completion` to `callback` on the coordinators and view models
- renamed `viewModelResult` to `viewModelAction`
- introduced back UserSession as a user specific service container
