Better solution for groups without a prefix

Route.php

@@ -73,7 +73,7 @@ abstract class Route
         );
     }
 
-    static function group(string $prefix = '', ?callable $callback = null)
+    static function group(string $prefix, callable $callback)
     {
         if (!str_starts_with(
             $_SERVER['REQUEST_URI'],

example.php

@@ -51,7 +51,7 @@ App::group('/test', function() {
         fn() => print('Testing 123'));
     
     // you may also define a group without a prefix
-    App::group(callback: function() {
+    App::group('', function() {
         App::get('/test',
             fn() => print('Testing 456'));
     });