Restore 3.x username suggestion behavior

[a-dows]

Pitch

Since updating to v4.0.2+hometown-1.1.0, the web interface's suggested usernames to tag in a post (shown when typing the @ character and waiting) appear to weight follower count, rather than followers/accounts you follow first.

The original sorting should be restored.

Motivation

Accounts you follow are far more likely to be tagged or interacted in a new post than a random high-follower-count account.

[dariusk]

Mostly a note for future me, there is more discussion here

https://friend.camp/@darius/109638046110736281

[dariusk]

Looks like I need to revert this change: mastodon#19251

Nope, I just needed to add a ranking order based on following

[dariusk]

Also made a PR on Mastodon mastodon#22956

[dariusk]

For the record, after consulting with Eugen, we came up with a better fix: 15e78b9