Size upgrade, wowie! (I figure sharing services probably prefer a higher-resolution image, they're not very big, and to then scale them down for the application-specific use case & device.)
Meta tags are a bit tricky in apps built with `create-react-app`! While some bots like Google are able to render the full page when crawling, not all bots are. Most will just see the empty-ish index.html that would normally load up the application.
But we want outfit sharing to work! And be cool! And use our new outfit thumbnails!
In this change, we add a new server-side rendering API route to handle `/outfits/:id`.
It's very weak server-side rendering: it just loads index.html, and makes a few small tweaks inside the `<head>` tag. But it should be enough for sharing to work in clients that support the basics of Open Graph, which I think most major providers respect! (I know Twitter has their own tags, but it also respects the basics of OG, so let's see whether there's anything we end up _wanting_ to tweak or not!)
