code: func AppCreatedPathFromStage1Rootfs(rootfs, appName string) string {
  	return filepath.Join(AppsStatusesPathFromStage1Rootfs(rootfs), fmt.Sprintf("%s-created", appName))
  }
docs: // AppCreatedPathFromStage1Rootfs returns the path of the ${appname}-created file,
  // which is used to record the creation timestamp of the app.
  // It receives the stage1 rootfs as parameter instead of the pod root.