- 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.
- Added StaffController for managing clinic staff, including listing, creating, updating, and toggling staff status.
- Created ClinicStaff entity and repository for staff data handling.
- Developed SubscriptionController to manage subscription plans and periods, including trial subscriptions.
- Introduced SubscriptionPlan, SubscriptionPeriod, and ClinicSubscription entities for subscription management.
- Implemented SubscriptionService for handling subscription logic, including trial activation and subscription creation from payments.
- Added necessary repositories for subscription entities to facilitate data access and manipulation.