test(e2e): align assertions with i18n fix — French→English labels

- us7: "Nouvelle simulation" → "New simulation" (3 assertions)
- us4: "Nouvelle simulation" → "New simulation" (1 assertion)
- us9: "Simulation pas encore en revue" → "Simulation not yet ready for review" (1 assertion)
- us11: "Marquer en revue" → "Mark for review" (6 assertions), "Clôturer" → /^close$/i (7 assertions)
- us12: "Supprimer" → /^delete$/i (4 assertions), "Supprimer la simulation" → "Delete simulation" (1 assertion)

No other French strings found in e2e/tests/. Suite: 68/68 pass.

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

e2e/tests/us4-engagements.spec.ts

@@ -265,9 +265,9 @@ test.describe('US-4 — engagement CRUD', () => {
     await expect(page.getByRole('heading', { name: /AC-4.9 detail target/i })).toBeVisible();
     // Sprint 2 replaced the placeholder with the real SimulationList — covered by AC-7.5.
     await expect(page.getByRole('heading', { name: /simulations/i })).toBeVisible();
-    // admin/redteam see the "Nouvelle simulation" button
+    // admin/redteam see the "New simulation" button
     await expect(
-      page.getByRole('link', { name: /nouvelle simulation/i }),
+      page.getByRole('link', { name: /new simulation/i }),
     ).toBeVisible();
   });
 });