Refactor the Filament admin panel structure by adjusting navigation sorting
across various resources to improve usability and logical grouping.
- Reorder navigation items in 'مالی' (Finance), 'تنظیمات' (Settings),
and 'عملیات' (Operations) groups.
- Hide `PriceTestPage` from the main navigation sidebar.
- Adjust sidebar width and max content width in `AdminPanelProvider`.
- Add custom CSS asset for Filament styling.
Implement a comprehensive financial management suite within the Filament
admin panel, including new resources for payments and discount codes,
along with a financial dashboard.
- feat(ui): add Filament Dashboard with finance overview and transaction
widgets
- feat(ui): implement PaymentResource for monitoring gateway transactions
- feat(ui): complete DiscountCodeResource with full CRUD and filtering
- feat(wallet): add automatic wallet creation on balance retrieval
- fix(wallet): resolve null handling in isFrozen() and balance viewing
- fix(db): correct enum type from 'percent' to 'percentage' in
discount_codes migration
- fix(api): update pricing calculation endpoint to /api/v1/calculate
- test: add 21 new feature and service tests covering wallet, payment,
and discount logic
- chore: remove obsolete PaymentGatewayService and update project status
