test(e2e): adapt export specs to 7-column schema (Scénario/Test/...)

Update AC-29.2 (Markdown) to assert | Scénario | GFM table header.
Update AC-29.3 (CSV) to assert exact 7 FR column names instead of 'name'.
Update AC-31.4 (empty engagement) MD to assert table absent, CSV header
to assert exact 7 FR columns.
Drop unused sim1/sim2 vars and makeClient import (NIT cleanup).

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

e2e/tests/us31-export-robustness.spec.ts

@@ -16,9 +16,18 @@ import {
   deleteUserByUsername,
   ensureUser,
   login,
-  makeClient,
 } from '../fixtures/api';
 
+const CSV_HEADER_COLS = [
+  'Scénario',
+  'Test',
+  'Source de log',
+  'Commentaires SOC',
+  'Exécution',
+  'Logs remontés au SIEM',
+  'Cyber incident',
+];
+
 const ADMIN_USER = 'us31-admin';
 const PASS = 'us31-pass-strong!';
 
@@ -142,8 +151,10 @@ test.describe('US-31 — Export robustness', () => {
       );
       expect(response.status()).toBe(200);
       const text = await response.text();
-      // Must contain engagement name in the header section
+      // Engagement header section present
       expect(text).toContain('US31 empty engagement');
+      // With 0 simulations the GFM table is absent (no rows to render)
+      expect(text).not.toContain('| Scénario |');
     } finally {
       await deleteEngagement(adminTok, engagement.id);
     }
@@ -167,8 +178,9 @@ test.describe('US-31 — Export robustness', () => {
       // Count rows via RFC-4180-aware counter (handles embedded newlines in quoted cells)
       const rowCount = countCsvRows(text);
       expect(rowCount).toBe(1);
-      // The single row is the header; must contain 'name' column
-      expect(text.trim()).toContain('name');
+      // The single row is the header with exactly the 7 FR columns
+      const headerCells = text.trim().split(',').map((c) => c.trim().replace(/^"|"$/g, ''));
+      expect(headerCells).toEqual(CSV_HEADER_COLS);
     } finally {
       await deleteEngagement(adminTok, engagement.id);
     }