Simplify this plugin

[yooouuri]

function layouts(routes: any) {
  return routes.map(r => {
    const layout = r.meta?.layout ?? 'default'

    if (r.children !== undefined) {
      return {
        ...r,
        children: layouts(r.children),
      }
    }

    if (r.component !== undefined) {
      const component = h('div', [
        h('div', layout),
        h(defineAsyncComponent(() => r.component())),
      ])

      return {
        ...r,
        component,
      }
    }

    return r
  })
}

Instead of altering the route, just replace the component and "insert" the layout.

This should resolve #149, #144, #134