code: public function onInitializeApplication(): void
      {
          if (file_exists($this->projectDir.'/system/initialize.php')) {
              return;
          }
  
          (new Filesystem())
              ->copy(
                  __DIR__.'/../Resources/skeleton/system/initialize.php',
                  $this->projectDir.'/system/initialize.php',
                  true
              )
          ;
      }
docs: Adds the initialize.php file.