Add language-search component for Autre Langue input + active search in lists

Mirrors the mots-clé tag-search system: dropdown suggestions from
existing languages via HTMX, pill display with bin-icon remove buttons,
'Créer' option for new languages. Replaces the plain text input.

- New partial: templates/partials/form/language-search.php
- New fragment: public/partage/language-search-fragment.php
- Admin wrapper: public/admin/language-search-fragment.php
- Updated language-autre-fragment to return just the required asterisk indicator
- Updated both controllers to handle language_autre as array (pill-based)
  with backward-compatible string path
- Updated edit form to compute selectedOtherLanguages from DB
- Registered new route in partage/index.php
- Fix CSV importer: split comma-separated language column into individual entries
- Add htmx active search to admin index, title line-clamp, predefined languages only in checkboxes
- Admin index: filter form now uses htmx triggers (input delay:300ms on search,
  change on selects) to actively search without page reload
- Sort links include hx-push-url for back-button support
- Added loading indicator bar (.admin-search-indicator)
- Title column: line-clamp at 2 lines with overflow hidden, native title attr
  tooltip for full text
- Language checkboxes now show only 3 predefined languages (Français, Anglais,
  Néerlandais); all others go via the Autre langue search component
- Added Database::getPredefinedLanguages() and excluded predefined from
  language-search-fragment suggestions
- Included hidden sort/dir inputs in table-wrap so sort state preserved across
  filter changes
- Fix language-search: block 'Créer' for predefined languages in dropdown
  The 'Créer' option in the language-search dropdown now also checks against the
  predefined set (français, anglais, néerlandais) to avoid offering creation of
  languages that already exist as checkboxes.

app/src/Controllers/ThesisCreateController.php

@@ -114,7 +114,7 @@ class ThesisCreateController
             'orientations'        => $this->db->getAllOrientations(),
             'apPrograms'          => $this->db->getAllAPPrograms(),
             'finalityTypes'       => $this->db->getAllFinalityTypes(),
-            'languages'           => $this->db->getAllLanguages(),
+            'languages'           => $this->db->getPredefinedLanguages(),
             'formatTypes'         => $this->db->getAllFormatTypes(),
             'licenseTypes'        => $this->db->getAllLicenseTypes(),
             'enabledAccessTypes'  => $this->db->getEnabledFormAccessTypes(),
@@ -467,8 +467,16 @@ class ThesisCreateController
         $languageIds = isset($post['languages']) && is_array($post['languages'])
             ? array_map('intval', $post['languages'])
             : [];
-        $autreRaw = trim($post['language_autre'] ?? '');
-        if ($autreRaw !== '') {
+        // language_autre: pill-based component sends an array; also handle legacy comma-separated string
+        $autreRaw = $post['language_autre'] ?? '';
+        if (is_array($autreRaw)) {
+            foreach ($autreRaw as $langName) {
+                $langName = trim($langName);
+                if ($langName !== '') {
+                    $languageIds[] = $this->db->getOrCreateLanguage($langName);
+                }
+            }
+        } elseif (is_string($autreRaw) && trim($autreRaw) !== '') {
             foreach (array_map('trim', explode(',', $autreRaw)) as $langName) {
                 if ($langName !== '') {
                     $languageIds[] = $this->db->getOrCreateLanguage($langName);