Improve @mention Auto-fill Suggestions

With the new(ish) comment box and user selection pop-ups, some of the shortcuts my teammates and I used to quickly select each other stopped working as well. Most of these shortcuts revolved around typing the person's email instead of their name since those were unique faster. With the new comment box, the suggestions seem to place higher priorities on fuzzy matches than on exact stemming matches on the email.

A couple of examples:

• One of my co-worker's email starts with smiller and we also have a group of people with the word "Small" in the group name. The auto-fill for @smill prioritizes the group that fuzzy matches over the user that stem matches on email.
• Another co-worker's email starts with emilner and auto-fill for @emiln has several Emilys before the co-worker I want.

Related, deactivated accounts seem to have a higher priority (they appear lower in the list closer to the comment box) than active accounts that match about the same. Deactivated (not unavailable which looks similar), to me would always be a lower match than active accounts and should be further away from the default selection.