Implement extension request and gift functionalities in billing system

- Added new endpoints for creating and managing extension requests, allowing users to request billing period extensions.
- Implemented admin approval processes for extension requests via Telegram, including inline buttons for approval and rejection.
- Introduced a gifting feature for admins to grant additional billing days directly to users without a request.
- Updated the support ticket model to accommodate extension requests and their associated properties.
- Enhanced the Telegram notifier to inform admins of new extension requests and notify users of approval or rejection.
- Updated frontend components to support the new extension request and gifting functionalities, including user interfaces for managing these features.
- Revised API documentation to reflect the new endpoints and their usage in the billing context.

backend/src/PnvPanel.Application/Support/CreateRoleRequest/CreateRoleRequestTicketCommandHandler.cs

@@ -108,6 +108,7 @@ public sealed class CreateRoleRequestTicketCommandHandler(
             ticket.ProposedRoleName,
             ticket.ProposedMaxConfigs,
             ticket.ProposedMaxIpLimit,
+            ticket.RequestedDays,
             ticket.CreatedAt,
             [commentDto]
         );