- Add OAuth SSO provider configuration types (OAuthSsoProviderConfig, OAuthSsoConfig)
- Create OAuth SSO service with support for Google, Microsoft, GitHub, and custom OIDC providers
- Implement OAuth SSO controller with endpoints for SSO configuration, login initiation, and callback handling
- Add routes for /api/auth/sso/* endpoints
- Update User entity and DAOs to support OAuth-linked accounts (oauthProvider, oauthSubject, email, displayName, avatarUrl)
- Update SystemConfig entity to include oauthSso field
- Update migration utility to handle OAuth SSO configuration and user fields
- Add OAuth callback page for frontend token handling
- Update LoginPage with SSO provider buttons and hybrid auth support
- Add i18n translations for OAuth SSO (English and Chinese)
- Add comprehensive tests for OAuth SSO service (13 new tests)
Co-authored-by: samanhappy <2755122+samanhappy@users.noreply.github.com>
