Occassional scroll position jump on new threads

[McManning]

Repro:

• Select some text
• Start a new thread
• Do this over and over until you run into the issue (lol).

Basically, since the thread's Tiptap instance has keyboard focus on mount and the thread is usually in mid transit down the page due to our translateY rule telling to hurry down to the target anchor - there's a chance that the browser will attempt to focus on the element when it's somewhere up higher on the page before the animation has settled.

Lazy solution: Focus delay that's longer than the animation + packing speed.

Better solution: TBD.