- Add complete notifications management view with:
- Service status display (Discord, Telegram)
- Test notification functionality
- Service management (delete/disable)
- Filter settings display (case sensitive/insensitive)
- Update API types to match current backend structure
- Fix NotificationFilters type (remove deprecated fields)
- Update page title from 'Vite + React + TS' to 'Leggen'
- Replace Vite favicon with custom Leggen favicon
- Add notifications tab to main navigation
- Ensure full API compatibility with current backend
- Add missing /api/v1/balances endpoint to backend
- Update frontend Account type to match backend AccountDetails model
- Add currency validation with EUR fallback in formatCurrency function
- Update AccountsOverview, TransactionsList, and Dashboard components
- Fix balance calculations to use balances array structure
- All pre-commit checks pass
