Toasts fade in 1-4s, so anything that scrolled past was gone. Notifications now retains
every pushed alert in a capped (100) ring buffer with a wall-clock epoch (AlertRecord) —
separate from the 5-item live-toast deque — plus a monotonic total_pushed_ counter.
A bell in the status-bar right cluster opens an upward popup listing recent alerts
newest-first: severity icon + colour (reusing the toast palette), the message, and a
relative age (formatTimeAgoShort), with a Clear-all action. An unread dot on the bell,
coloured by the most-severe unseen alert, marks alerts that arrived since the panel was
last opened — driven by totalPushed() deltas so it survives capping/clearing.
Thread note: every push is on the UI thread (RPC results run as main-thread MainCb
callbacks), matching this class's existing lock-free model; documented as a
no-raw-worker-thread invariant.
New i18n keys (alerts_*). Build-clean; ctest 1/1 (adds testNotificationHistory: retention,
order, cap, monotonic counter, clear). Closes the QoL bundle and the Foundation tier.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>