docs: add about locale routes

Author: kenjis

docs/customization/route_config.md

@@ -1,6 +1,10 @@
 # Customizing Routes
 
-If you need to customize how any of the auth features are handled, you will likely need to update the routes to point to the correct controllers. You can still use the `service('auth')->routes()` helper, but you will need to pass the `except` option with a list of routes to customize:
+## Change Some Routes
+
+If you need to customize how any of the auth features are handled, you will likely need to update the routes to point to the correct controllers.
+
+You can still use the `service('auth')->routes()` helper, but you will need to pass the `except` option with a list of routes to customize:
 
 ```php
 service('auth')->routes($routes, ['except' => ['login', 'register']]);
@@ -12,3 +16,36 @@ Then add the routes to your customized controllers:
 $routes->get('login', '\App\Controllers\Auth\LoginController::loginView');
 $routes->get('register', '\App\Controllers\Auth\RegisterController::registerView');
 ```
+
+After customization, check your routes with the [spark routes](https://codeigniter.com/user_guide/incoming/routing.html#spark-routes) command.
+
+## Use Locale Routes
+
+You can use the `{locale}` placeholder in your routes
+(see [Locale Detection](https://codeigniter.com/user_guide/outgoing/localization.html#in-routes)).
+
+```php
+$routes->group('{locale}', static function($routes) {
+    service('auth')->routes($routes);
+});
+```
+
+The above code registers the following routes:
+
+```text
++--------+----------------------------------+--------------------+--------------------------------------------------------------------+----------------+---------------+
+| Method | Route                            | Name               | Handler                                                            | Before Filters | After Filters |
++--------+----------------------------------+--------------------+--------------------------------------------------------------------+----------------+---------------+
+| GET    | {locale}/register                | register           | \CodeIgniter\Shield\Controllers\RegisterController::registerView   | session        | toolbar       |
+| GET    | {locale}/login                   | login              | \CodeIgniter\Shield\Controllers\LoginController::loginView         | session        | toolbar       |
+| GET    | {locale}/login/magic-link        | magic-link         | \CodeIgniter\Shield\Controllers\MagicLinkController::loginView     | session        | toolbar       |
+| GET    | {locale}/login/verify-magic-link | verify-magic-link  | \CodeIgniter\Shield\Controllers\MagicLinkController::verify        | session        | toolbar       |
+| GET    | {locale}/logout                  | logout             | \CodeIgniter\Shield\Controllers\LoginController::logoutAction      | session        | toolbar       |
+| GET    | {locale}/auth/a/show             | auth-action-show   | \CodeIgniter\Shield\Controllers\ActionController::show             | session        | toolbar       |
+| POST   | {locale}/register                | register           | \CodeIgniter\Shield\Controllers\RegisterController::registerAction | session        | toolbar       |
+| POST   | {locale}/login                   | »                  | \CodeIgniter\Shield\Controllers\LoginController::loginAction       | session        | toolbar       |
+| POST   | {locale}/login/magic-link        | »                  | \CodeIgniter\Shield\Controllers\MagicLinkController::loginAction   | session        | toolbar       |
+| POST   | {locale}/auth/a/handle           | auth-action-handle | \CodeIgniter\Shield\Controllers\ActionController::handle           | session        | toolbar       |
+| POST   | {locale}/auth/a/verify           | auth-action-verify | \CodeIgniter\Shield\Controllers\ActionController::verify           | session        | toolbar       |
++--------+----------------------------------+--------------------+--------------------------------------------------------------------+----------------+---------------+
+```