## Payment Analytics Integration
- Add 5 new API endpoints for payment metrics:
- /api/analytics/payments-over-time - trend visualization
- /api/analytics/payments-by-status - status distribution
- /api/analytics/payments-by-method - method breakdown
- /api/analytics/payment-summary - statistics with period comparison
- /api/analytics/revenue-vs-payments - collection rate tracking
- Integrate payment data into analytics dashboard with 4 new charts
- Add payment metrics to reports page (total, count, fees, net received)
- Update summary endpoint to include payment statistics
## UI/UX Improvements
- Standardize form styling across all payment templates
- Replace inconsistent Tailwind classes with form-input utility
- Update card backgrounds to use card-light/card-dark
- Fix label spacing to match application patterns
- Ensure consistent border colors and backgrounds
- Replace browser confirm() with system-wide modal for payment deletion
- Consistent danger variant with warning icon
- Keyboard support (Enter/Escape)
- Dark mode compatible
- Clear messaging about impact on invoice status
## Technical Changes
- Import Payment and Invoice models in analytics and reports routes
- Add proper admin/user scoping for payment queries
- Maintain responsive design across all new components
Closes payment tracking phase 2 (analytics & polish)
Dries Peeters