processStatusNotification re-notified on any reworded status message;
align it with the quota notifications so only a new incident or a
worsened severity fires.

updateSelectedProvider re-ran autoSelectedProviderIndex() on every
refresh, clobbering an Overview selection the user had explicitly
picked. Preserve it once selection is initialized and Overview is the
active view.

Add regression assertions for both.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>