feat(cat-voices): registration seed phrase step

[damian-molinski]

Description

• In future we should have more gradual control of BlocBuilder , possible by having only one final class RegistrationState with step in it.
• Remove public KeychainCreationController and WalletLinkController and make them internal for RegistrationBloc.
• Event based communication.
• Generic SeedPhrasePicture widget which can animate as state changes

Related Issue(s)

Part of #816

Screenshots

• My code follows the style guidelines of this project
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• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream module

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 253/253}$ | ${\color{red}Fail: 0/253}$ |