Buttons for per-package / per-type close all; temporary mute; move to bottom

[saizai]

Please add buttons, replacing 'close all' and 'close this' (x in corner):

that are:

1. scoped to all notifications
   • shown above all notifications
2. 📦 scoped to the generating package
3. ≈ scoped to the underlying error / notification type (e.g. "Error communicating with GitHub"; network errors; config/setup request; restart request; 'finished doing the thing' info; etc)
4. ① scoped to current notification
   • (2-4) shown on a given notification

and which:

1. Ｘ close all for that scope
   • don't show for scopes 1-3 if scope size is 1
2. 🔕 close all and mute for that scope, suppressing further notifications for X minutes [configurable, default 1?]
   • don't show for scope 4 (no future-defined scope to mute)
3. ⬇ move to bottom of the notifications stack
   • don't show if all notifications are visible on screen and # notifications < X [default 5?]
   • don't show for scopes 1-3 if scope size is 1

Button position should be maintained even if others aren't shown (for muscle memory), and these should all be simple icons (not text, except alt-text).

This is up to 3 buttons at top + 3x3 per notification total (vs the current 1 + 1), but probably less than that most of the time.

'Move to bottom" would help when there are a lot of notifications, as a "deal with it later, remove the clutter first" option.

Related to:
#12 #116 #88 #90