feat(audit): enchufar audit en handlers de Rol (UDT-010 B8)

4 command handlers del módulo Roles + Permisos ahora auditan:

| Handler                              | Action                 |
|--------------------------------------|------------------------|
| CreateRolCommandHandler              | rol.create             |
| UpdateRolCommandHandler              | rol.update             |
| DeactivateRolCommandHandler          | rol.deactivate         |
| AssignPermisosToRolCommandHandler    | rol.permisos_update    |

Mismo patrón que B7 (using block + post-commit reads outside scope).

Metadata:
- rol.create: after={Codigo, Nombre, Descripcion}
- rol.update: {before, after} diff
- rol.permisos_update: {before, after} con arrays de codigos ordenados

AssignPermisosToRolCommandHandler captura 'before' leyendo
GetByRolCodigoAsync antes del TransactionScope para poder emitir el diff.

4 test classes actualizados con mock de IAuditLogger.

Suite: 378/378 Application.Tests + 141/141 Api.Tests = 519/519 passing.

Refs: sdd/udt-010-auditoria-trazabilidad/{spec#REQ-RM-AUD, design, tasks#B8}

tests/SIGCM2.Application.Tests/Roles/Deactivate/DeactivateRolCommandHandlerTests.cs

@@ -1,5 +1,6 @@
 using NSubstitute;
 using SIGCM2.Application.Abstractions.Persistence;
+using SIGCM2.Application.Audit;
 using SIGCM2.Application.Roles.Deactivate;
 using SIGCM2.Domain.Entities;
 using SIGCM2.Domain.Exceptions;
@@ -9,6 +10,7 @@ namespace SIGCM2.Application.Tests.Roles.Deactivate;
 public class DeactivateRolCommandHandlerTests
 {
     private readonly IRolRepository _repository = Substitute.For<IRolRepository>();
+    private readonly IAuditLogger _audit = Substitute.For<IAuditLogger>();
     private readonly DeactivateRolCommandHandler _handler;
 
     private static Rol RolActive(string codigo, int id = 10)
@@ -19,7 +21,7 @@ public class DeactivateRolCommandHandlerTests
 
     public DeactivateRolCommandHandlerTests()
     {
-        _handler = new DeactivateRolCommandHandler(_repository);
+        _handler = new DeactivateRolCommandHandler(_repository, _audit);
     }
 
     [Fact]