Add social media preview

> example from [opg](https://ogp.me/):
> 
> ```
> <meta property="og:title" content="The Rock" />
> <meta property="og:type" content="video.movie" />
> <meta property="og:url" content="https://www.imdb.com/title/tt0117500/" />
> <meta property="og:image" content="https://ia.media-imdb.com/images/rock.jpg" />
> ```