- Add ZarinpalService for production payment gateway
- Add MockZarinpalService for testing without real merchant ID
- Add MockGatewayController for simulating payment page
- Add beautiful mock gateway UI with RTL support
- Update PaymentController to switch between mock/real based on config
- Fix double-click bug: prevent re-processing completed transactions
- Add payment-result page with success/failure UI
- All API endpoints tested successfully:
* balance, transactions, activity-log
* admin-adjust (deposit/withdrawal)
* freeze/unfreeze
* online payment redirect + callback + verify
- Wallet balance verified: 67,700,000 IRR after all transactions
- 5 transactions recorded with correct gateways (manual/zarinpal)
Closes: Payment gateway integration for Phase 2
Add Zarinpal configuration options and implement the core payment
infrastructure, including the Payment model, migration, service
layer, and API controller.