Fase 1: Inicialización del Backend .NET 10, Configuración de Dapper, Autenticación JWT y Entidades Base

src/SIGCM.Infrastructure/Services/AuthService.cs

@@ -0,0 +1,27 @@
+using SIGCM.Application.Interfaces;
+using SIGCM.Domain.Interfaces;
+
+namespace SIGCM.Infrastructure.Services;
+
+public class AuthService : IAuthService
+{
+    private readonly IUserRepository _userRepo;
+    private readonly ITokenService _tokenService;
+
+    public AuthService(IUserRepository userRepo, ITokenService tokenService)
+    {
+         _userRepo = userRepo;
+         _tokenService = tokenService;
+    }
+
+    public async Task<string?> LoginAsync(string username, string password)
+    {
+        var user = await _userRepo.GetByUsernameAsync(username);
+        if (user == null) return null;
+        
+        bool valid = BCrypt.Net.BCrypt.Verify(password, user.PasswordHash);
+        if (!valid) return null;
+
+        return _tokenService.GenerateToken(user);
+    }
+}