Implement support ticket system with role request and bug report functionalities

- Introduced a new support ticket system allowing users to submit bug reports and role requests.
- Implemented endpoints for creating, updating, and managing support tickets, including file attachments.
- Enhanced Telegram bot integration to handle role requests directly within the bot, enabling admins to approve or reject requests without accessing the website.
- Updated database schema to include support ticket entities and their relationships.
- Improved API documentation to reflect new support ticket endpoints and their usage.
- Added necessary localization for support ticket features in both Russian and English.

backend/src/PnvPanel.Application/Support/TicketAttachmentDto.cs

@@ -0,0 +1,3 @@
+namespace PnvPanel.Application.Support;
+
+public sealed record TicketAttachmentDto(Guid Id, string FileName, string ContentType, long SizeBytes);