feat: Implement create account

[apomalyn]

Requirements

• Implement Firebase Auth account registration for Anonymous.
• Register the new user on the API
• Link the UI to allow account registration

What needs to be done

• Implement in the UserRepository.register():
  • creation of an anonymous account following the Firebase documentation
  • call UserService.getUser to create the user in the API and in the local database
  • Set the returned user as the connected one
• Update the Landing view model, on Getting started pressed to create an anonymous account

Dependencies

Child of #130

Depends on:

• 135

• 132

• API # 16 https://github.com/RoadTripMoustache/kana_to_kanji_api/issues/16

Dev notes

• Firebase auth documentation

[Adaendra]

@apomalyn I can implement this process, but were is it used ? An anonymous account don't need to have an email/password, and we don't have a button/link to allow the user to use the application without being logged in.

So, where will be the link/button to allow the user to create an annonymous account ?

If we want to have the user/password only, we should use this.

[apomalyn]

The register (account creation) is different than linkAccount (#138). When a user lands on the application for the first time, it will be redirected to the LandingView (#132) and the Getting started button will trigger the register, creating an anonymous account and the "link" button/banner (#146) will be available on the profile

[Adaendra]

@apomalyn in case of an error in the registration, what are we going to do ?

Also, we need to change the way the app is started. Currently we start on the splash screen which initialize the app, but we won't be able to leave it if we don't have a correct token to call the API.

[apomalyn]

in case of an error in the registration, what are we going to do?

The only reason registration would fail is if the API or Firebase isn't available. In both cases, I guess a classic error message (in a toast) should be enough

Also, we need to change the way the app is started. Currently we start on the splash screen which initialize the app, but we won't be able to leave it if we don't have a correct token to call the API.

Yes, we need to update the splash screen, I see 2 options:

1. Update the splash screen to first check if a silent login is possible, then go to initialization or to the login screen
2. Create a new screen Initialization which would contain the actual splash and update the latter to check if silent login is possible