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/TicketAuthorization.cs

@@ -0,0 +1,13 @@
+using PnvPanel.Application.Common.Interfaces;
+
+namespace PnvPanel.Application.Support;
+
+internal static class TicketAuthorization
+{
+    // Совпадает со значением Infrastructure.Identity.RoleNames.Admin — см. пояснение в
+    // CreateRoleRequestTicketCommandHandler (Application не может ссылаться на Infrastructure).
+    private const string AdminRoleName = "admin";
+
+    public static bool IsAdmin(CurrentUserProfile? profile) =>
+        profile is not null && profile.Role.Equals(AdminRoleName, StringComparison.OrdinalIgnoreCase);
+}