feat(frontend): add Angular 21 SPA with Material Design
Core:
- Apollo Angular for GraphQL integration
- Student and Enrollment services
- Connectivity monitoring with health checks
- Error handling with user-friendly messages
Features:
- Students: list, create, edit, delete
- Enrollment: subject selection with validation feedback
- Classmates: view students in shared subjects
Shared Components:
- ConfirmDialog, EmptyState, LoadingSpinner
- ConnectivityOverlay for offline detection
- Custom pipes (credits, initials)
UI:
- Angular Material with custom theme
- Responsive layout with navigation
- Real-time validation feedback
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
e30424cd1f