feat(payment): add refund and reversal functionality to payment gateways

- Implemented `refund` and `reverse` methods in `PaymentGatewayInterface`.
- Added `PaymentRefundResult` class to handle refund operation results.
- Enhanced `MockGateway` and `SepGateway` to support refund and reversal operations.
- Updated `PaymentManager` to include `refundPayment` and `reversePayment` methods for handling refunds and reversals in transactions.
- Modified `ClinicSubscriptionRepository` and `SubscriptionService` to manage subscriptions during refunds.
- Added admin API endpoints for processing refunds and reversals.
- Updated security headers to allow form actions to the sandbox environment.
- Documented the new refund and reversal features in the API documentation.

src/Shared/EventSubscriber/SecurityHeadersSubscriber.php

@@ -41,7 +41,7 @@ class SecurityHeadersSubscriber implements EventSubscriberInterface
                 $isPaymentPage
                     ? "default-src 'none'; style-src 'unsafe-inline'; script-src 'unsafe-inline'; "
                         . "font-src https://cdn.jsdelivr.net data:; img-src data:; "
-                        . "form-action https://*.shaparak.ir; base-uri 'none'"
+                        . "form-action https://*.shaparak.ir https://sandbox.banktest.ir; base-uri 'none'"
                     : "default-src 'none'"
             );
         }