The OpenTUI engine received the gateway's credits/usage notices but
mis-rendered them as scrolling inline transcript cards with no lifecycle.
Render them instead as a persistent, level-tinted chrome banner pinned
directly above the status bar, matching the Ink engine — no gateway/agent
changes (the wire + credits policy stay the source of truth).
- backgroundActivity.ts: widen level to include `success` (was silently
dropped to info) + add isChromeNotice() (kind sticky|ttl) discriminator.
- store.ts: port the Ink turnController notice lifecycle — showNotice/
applyNotice/clearNotice/flushPendingNotice/clearNoticeState, a single TTL
timer (latest-wins, id-guarded), mid-turn hold + turn-end reveal (the
three end sites: message.complete, gateway.exited, error), flash-and-yield
for credits.usage/grant_spent at message.start, and a notice reset on
clearTranscript + commitSnapshot so it can't bleed across sessions. Route
notification.show by kind: sticky|ttl -> chrome banner, everything else
(process/background completion cards) -> existing inline path, unchanged.
Distinct clones for notice vs lastNotification (createStore aliasing).
- noticeBanner.tsx + App.tsx: a single sticky row above the status bar,
text rendered verbatim (already glyphed by the policy), tinted by level,
width-truncated so it can never wrap and push the composer.
Tests: statusNotice.test.ts (lifecycle/routing/TTL/flash-and-yield),
noticeBanner.test.tsx (render/color/truncation), backgroundActivity +
render additions. npm run check OK (768 tests).
8e3b320eb8