refactor: prepare Android ViewModel creation boundary [WPB-23495]

[Garzas]

https://wearezeta.atlassian.net/browse/WPB-23495

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What's new in this PR?

Summary

Prepares the old login ViewModel creation boundary for the Metro migration.

This PR removes direct SavedStateHandle.navArgs() usage from the old login base/email/SSO ViewModels and passes LoginNavArgs explicitly through assisted ViewModel creation. It also moves saved login input persistence behind a small LoginSavedInputStore boundary so the ViewModels no longer own the Android saved-state mechanism directly.

Changes

• Add wireViewModel(...) helpers for assisted Hilt ViewModel creation from Compose.
• Change LoginViewModel, LoginEmailViewModel, and LoginSSOViewModel to receive explicit LoginNavArgs.
• Add LoginSavedInputStore and SavedStateLoginSavedInputStore.
• Update old login and new-login password call sites to create assisted LoginEmailViewModel / LoginSSOViewModel with nav args.
• Keep SSO Nomad behavior intact while moving auto-login args handling out of direct SavedStateHandle.navArgs() reads.

[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud