Improve recap page + fix CSV import for jury roles

recapitulatif.php (partage):
- Center .thanks-success and add bottom margin/padding
- Display ALL fields: identifier, synopsis, languages, formats,
  jury (all roles), baiu link, license, access type
- Add validation notice asking user to verify info, with
  xamxam@erg.be contact link (email obfuscated)

StudentEmail:
- Add 'Note contextuelle' and license_custom to email recap
- Rename 'Promoteur·ice(s)' to 'Promoteur·ice(s) interne'
- Change email message to ask student to verify info + contact
  for errors

CSV export/import:
- Add 3 new CSV columns: Lecteur·ice(s) interne,
  Lecteur·ice(s) externe, Promoteur·ice(s) ULB
- Export splits supervisors by role/is_external/is_ulb into
  separate columns
- Import inserts supervisors with correct role, is_external,
  and is_ulb flags (was: all treated as generic supervisors)
- Add header matching for short distinguishers (ulb, externe)
  via str_contains fallback

app/public/assets/css/form.css

@@ -797,12 +797,41 @@ a.recap-file-name:hover {
 .partage-recap {
   display: flex;
   flex-direction: column;
+  align-items: center;
   gap: var(--space-l);
+  padding-bottom: var(--space-3xl);
+  margin-bottom: var(--space-2xl);
+}
+
+.partage-recap .thanks-success {
+  text-align: center;
+}
+
+.recap-validate-notice {
+  text-align: center;
+  font-size: var(--step--1);
+  color: var(--text-secondary);
+  background: color-mix(in srgb, var(--accent-primary) 8%, transparent);
+  border: 1px solid color-mix(in srgb, var(--accent-primary) 20%, transparent);
+  border-radius: 8px;
+  padding: var(--space-s) var(--space-m);
+  max-width: 560px;
+}
+
+.recap-validate-notice p {
+  margin: 0;
+}
+
+.recap-validate-notice a {
+  color: var(--accent-primary);
+  font-weight: 600;
 }
 
 .recap-section {
   border-top: 1px solid var(--border-primary);
   padding-top: var(--space-m);
+  width: 100%;
+  max-width: 620px;
 }
 
 .recap-section h2 {