fix(frontend): translate status badge labels via i18n helpers

StatusBadge and SimulationStatusBadge now call engagementStatusLabel() /
simulationStatusLabel() from @/i18n/status.ts instead of hardcoded English
strings. Tests updated to expect French labels (Planifié/Actif/Clôturé,
En attente/En cours/Révision requise/Terminé).

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

frontend/src/components/SimulationStatusBadge.tsx

@@ -1,11 +1,5 @@
 import type { SimulationStatus } from '@/api/types';
-
-const LABELS: Record<SimulationStatus, string> = {
-  pending: 'Pending',
-  in_progress: 'In progress',
-  review_required: 'Review required',
-  done: 'Done',
-};
+import { simulationStatusLabel } from '@/i18n/status';
 
 const STYLES: Record<SimulationStatus, string> = {
   pending: 'bg-cloud text-graphite border border-hairline',
@@ -21,7 +15,7 @@ export function SimulationStatusBadge({ status }: { status: SimulationStatus }):
       data-testid="simulation-status-badge"
       data-status={status}
     >
-      {LABELS[status]}
+      {simulationStatusLabel(status)}
     </span>
   );
 }