[Feature request] add `@vuepress/layouts`

[Mister-Hope]

Clear and concise description of the problem

Some layouts are commonly needed by users and themes.

Suggested solution

We would like to provide a package containing common layouts:

1. portfolio, like https://theme-hope.vuejs.press/zh/demo/portfolio-home.html
2. masonry, https://theme-plume.vuejs.press/guide/components/card-masonry/
3. friend link: https://theme-plume.vuejs.press/friends/
4. cards: https://theme-plume.vuejs.press/guide/markdown/card/#%E7%A4%BA%E4%BE%8B

[github-actions]

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[github-actions]

This issue is marked as stale because it has not had recent activity. Issues marked with stale will be closed if they have no activity within 7 days.

[github-actions]

This issue is marked as stale because it has not had recent activity. Issues marked with stale will be closed if they have no activity within 7 days.