test: add accessibility coverage for the status-recommendation panel

Adds aria-live="polite" to the status-conflict panel (matching the existing
resolved-issue success-panel convention) so the applied-status confirmation is
announced to screen readers, and a Playwright test covering: keyboard-only
activation of both the "Review recommendation" and "Change status to X" actions,
reduced-motion emulation, and that status is never conveyed by colour alone (the
badge always carries its own localized text).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

frontend/src/pages/DataQualityIssueDetail.tsx

@@ -566,7 +566,7 @@ function VehicleStatusConflictPanel({ issue, onResolved }: { issue: IssueDetail;
     recommendation.safe_to_apply;
 
   return (
-    <section className="panel" aria-labelledby="status-conflict-heading">
+    <section className="panel" aria-labelledby="status-conflict-heading" aria-live="polite">
       <SectionHeading
         headingId="status-conflict-heading"
         title={t("detail.vehicleStatusConflict.heading")}