- Merge OIDC authentication fixes from 3877e90:
* Enhanced JWKS discovery mechanism with multiple backup URLs
* Better support for non-standard OIDC providers (Authentik, etc.)
* Improved error handling for "Failed to get user information"
- Migrate to unified Sonner toast notification system:
* Replace custom success/error state management
* Remove redundant alert state variables
* Consistent user feedback across all components
- Improve code quality and function naming conventions
- PRESERVE all existing i18n functionality and Chinese translations
🤖 Generated with Claude Code
Co-Authored-By: Claude <[email protected]>
