Follow-up of https://github.com/zed-industries/zed/pull/30015
* Restyles the dismiss and close buttons a bit: change the dismiss icon
and add tooltips with the bindings to both
* Allows ESC to clear any status that's in the activity indicator now,
if all notifications are cleared: this won't suppress any further status
additions though, so statuses may resurface later
Release Notes:
- Added a way to clear activity indicator
6e19c9b141