Port Mastodon's hashtag stats thing to glitch-soc.
This doesn't change how hashtags are ordered, and doesn't add a trending
hashtags section, but it does change how hashtag searches are rendered,
displaying a trend line alongside each hashtag.
This makes the clickable element an interactive element, but doesn't add
alt text and makes it not-obvious that you can click the elefriend. On
one hand, this goes against good practice; on the other hand, it's not
*supposed* to be obvious that you can click the elefriend.
Also lay some groundwork needed to interactively change the
glitchfriend.
The codebase uses "elefriend" because it's shorter and didn't require me
to realign the actions in actions/compose.js. Same idea, though.
