Fix images on the upload page appearing stretched (having the incorrect aspect ratio) when the image
is enlarged on Safari.
The fix is to set `aspect-ratio` and `height: intrinsic` to ensure the image is the right size. I
have no idea how this works or why it's necessary on Safari.
Fixes https://danbooru.donmai.us/forum_posts/227099.
Components are used to encapsulate common UI widgets used throughout the site. This includes things like comments, tag
lists, post thumbnails, paginators, and other things used repeatedly throughout the site. Components encapsulate a
widget's HTML, CSS, and Javascript together so that all the code for a component is in a single place.