feat: multi-ingress SSO flow - WPB-23281

[netbe]

WPB-23281 [iOS] Implement multi-ingress SSO flow

Issue

This PR adds multi-ingress SSO flow support for API v15.

• Checks first if email has an associated sso code and redirect to login

Testing

See details in ticket's comment

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Checklist

• Title contains a reference JIRA issue number like [WPB-XXX].
• Description is filled and free of optional paragraphs.
• Adds/updates automated tests.

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UI accessibility checklist

If your PR includes UI changes, please utilize this checklist:

• Make sure you use the API for UI elements that support large fonts.
• All colors are taken from WireDesign.ColorTheme or constructed using WireDesign.BaseColorPalette.
• New UI elements have Accessibility strings for VoiceOver.

[sonarqubecloud]

Quality Gate passed

Issues
0 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

[github-actions]

Test Results

110 tests   110 ✅  11s ⏱️
 22 suites    0 💤
  1 files      0 ❌

Results for commit 388c445.

Summary: workflow run #25740299314
Allure report (download zip): html-report-29926-feat_multi-ingress

[David-Henner]

thought: keeping determineAuthMethod at this level might help with having a high-level overview of the flow.

switch emailOrSSOCode {
  case let .email(email, domain):
       if let defaultSSOCode = try await defaultSSOCode(email: email, domain: domain) {
           return .loginViaSSO(code: defaultSSOCode)
       } else {
           return try await determineAuthMethod(email: email, domain: domain)
       }
   }
   // ...
}