Fix form field required states & missing fields per spec

- Admin add: add contact_public checkbox (matching edit form)
- All forms: formats checkbox-list now required
- All forms: jury promoteur·ice interne required, lecteur·ice interne/externe required
- All forms: licence select now required
- Admin edit: add E-mail de confirmation fieldset
- Partage: contact always visible when provided (no contact_public field)
- Partage: filter PACS from AP programs dropdown
- Server-side validation: formats, jury, licence required (create + edit controllers)
- Autofocus mappings for new validation errors
- No duplicate asterisks — verified across all rendered fields
- fix: add missing old() function in admin edit controller
- refactor: move admin email field to Backoffice as Contact interne, never send email
- Untrack admin.log (covered by .gitignore)

app/public/admin/edit.php

@@ -21,6 +21,11 @@ $autofocusField = App::consumeAutofocus();
 $helpBlocks = Database::getInstance()->getAllFormHelpBlocks();
 $helpFn = fn(string $key) => $helpBlocks[$key]['content'] ?? '';
 
+function old($key, $default = "") {
+    global $formData;
+    return isset($formData[$key]) ? htmlspecialchars($formData[$key]) : $default;
+}
+
 try {
     $ctrl = ThesisEditController::create();
     $view = $ctrl->load($thesisId);