- Created Toast component with slide-in animation for success/error/info/warning messages
- Created useToast hook for managing toast notifications globally
- Added ToastContext to App.tsx for sharing toast functionality across components
- Implemented ErrorBoundary component to catch and display React errors gracefully
- Updated RecipeDetailPage to show toast notifications for all operations (create, update, delete, tag management)
- Updated TagSelector to use toast notifications instead of alert()
- Added proper error handling for all API operations with user-friendly messages
- Added loading states for delete operation
- Verified: All 34 backend tests passing, frontend builds successfully