fix: nice-to-have polish — breadcrumbs, close button, status badges

- 7.1: Add deployment status badge (StatusDot + Badge) to AppsTab app
  list, sourced from catalog.deployment.status via slug lookup
- 7.3: Add X close button to top-right of exchange detail right panel
  in ExchangesPage (position:absolute, triggers handleClearSelection)
- 7.5: PunchcardHeatmap shows "Requires at least 2 days of data"
  when timeRangeMs < 2 days; DashboardL1 passes the range down
- 7.6: Command palette exchange results truncate IDs to ...{last8}
  matching the exchanges table display

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

ui/src/components/LayoutShell.tsx

@@ -489,7 +489,7 @@ function LayoutContent() {
     const exchangeItems: SearchResult[] = (exchangeResults?.data || []).map((e: any) => ({
       id: e.executionId,
       category: 'exchange' as const,
-      title: e.executionId,
+      title: `...${e.executionId.slice(-8)}`,
       badges: [{ label: e.status, color: statusToColor(e.status) }],
       meta: `${e.routeId} · ${e.applicationId ?? ''} · ${formatDuration(e.durationMs)}`,
       path: `/exchanges/${e.applicationId ?? ''}/${e.routeId}/${e.executionId}`,