Just moving more stuff over! I modernized Item's `as_json` method while
I was here. (Note that I removed the NC/own/want fields, because I
think the only other place this method is still called from is the
quick-add feature on the closet lists page, and I think it doesn't use
these fields to do anything: updating the page is basically a full-page
reload, done sneakily.)
Ok progress! We've moved the info about what bodies this fits, and
what zones it occupies, into a Rails API endpoint that we now load at
the same time as the other data!
We'll keep moving more over, too!
