Implement localization for API responses and error messages

- Added localization support for API responses in English and Spanish.
- Introduced a middleware to set the API locale based on the Accept-Language header.
- Updated various exception messages and validation responses to use localized strings.
- Created new language files for English and Spanish translations.
- Refactored existing code to replace hardcoded messages with localized strings.
- Added tests to verify localization functionality and response correctness.

app/Domains/Auth/Controllers/RegisterController.php

@@ -12,15 +12,17 @@ class RegisterController extends Controller
 {
     public function __construct(
         protected RegisterUserService $registerUserService,
-    ) {
-    }
+    ) {}
 
     public function __invoke(RegisterUserRequest $request): JsonResponse
     {
         $user = $this->registerUserService->register($request->validated());
 
         return UserResource::make($user)
-            ->additional(['message' => 'Usuario registrado correctamente.'])
+            ->additional([
+                'code' => 'auth.register_success',
+                'message' => __('api.auth.register_success'),
+            ])
             ->response()
             ->setStatusCode(201);
     }