Initial commit: HelpDesk ICHN - .NET 10 backend + Next.js 16 frontend

backend/HelpDesk.API/Services/IJwtService.cs

@@ -0,0 +1,10 @@
+using System.Security.Claims;
+using HelpDesk.Models.Enums;
+
+namespace HelpDesk.API.Services;
+
+public interface IJwtService
+{
+    string GenerateToken(Guid userId, string email, UserRole role);
+    ClaimsPrincipal? ValidateToken(string token);
+}