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/templates/admin/index-table.php

@@ -21,6 +21,10 @@ $sortArrow = function(string $col) use ($sortCol, $sortDir): string {
 
 <div id="admin-table-wrap">
 
+<!-- Hidden state for HTMX to preserve sort across filter changes -->
+<input type="hidden" name="sort" value="<?= htmlspecialchars($sortCol) ?>">
+<input type="hidden" name="dir"  value="<?= htmlspecialchars($sortDir) ?>">
+
 <!-- Meta bar: shows either nothing (default) or bulk actions on selection -->
 <div id="bulk-actions" class="admin-bulk-actions" style="display:none">
     <strong><span id="selected-count">0</span> TFE(s) sélectionné(s)</strong>
@@ -42,13 +46,13 @@ $sortArrow = function(string $col) use ($sortCol, $sortDir): string {
     <thead>
         <tr>
             <th scope="col"><input type="checkbox" onchange="toggleAll(this)"></th>
-            <th scope="col"><a href="<?= $sortLink('identifier') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('identifier')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML">ID<?= $sortArrow('identifier') ?></a></th>
-            <th scope="col"><a href="<?= $sortLink('title') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('title')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML">Titre<?= $sortArrow('title') ?></a></th>
+            <th scope="col"><a href="<?= $sortLink('identifier') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('identifier')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML" hx-indicator="#admin-search-indicator" hx-push-url="true">ID<?= $sortArrow('identifier') ?></a></th>
+            <th scope="col"><a href="<?= $sortLink('title') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('title')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML" hx-indicator="#admin-search-indicator" hx-push-url="true">Titre<?= $sortArrow('title') ?></a></th>
             <th scope="col">Auteur(s)</th>
-            <th scope="col"><a href="<?= $sortLink('year') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('year')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML">Année<?= $sortArrow('year') ?></a></th>
-            <th scope="col"><a href="<?= $sortLink('orientation') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('orientation')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML">Orientation<?= $sortArrow('orientation') ?></a></th>
-            <th scope="col"><a href="<?= $sortLink('ap_program') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('ap_program')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML">AP<?= $sortArrow('ap_program') ?></a></th>
-            <th scope="col"><a href="<?= $sortLink('is_published') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('is_published')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML">Publié<?= $sortArrow('is_published') ?></a></th>
+            <th scope="col"><a href="<?= $sortLink('year') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('year')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML" hx-indicator="#admin-search-indicator" hx-push-url="true">Année<?= $sortArrow('year') ?></a></th>
+            <th scope="col"><a href="<?= $sortLink('orientation') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('orientation')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML" hx-indicator="#admin-search-indicator" hx-push-url="true">Orientation<?= $sortArrow('orientation') ?></a></th>
+            <th scope="col"><a href="<?= $sortLink('ap_program') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('ap_program')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML" hx-indicator="#admin-search-indicator" hx-push-url="true">AP<?= $sortArrow('ap_program') ?></a></th>
+            <th scope="col"><a href="<?= $sortLink('is_published') ?>" class="admin-sort-link" hx-get="<?= htmlspecialchars($sortLink('is_published')) ?>" hx-target="#admin-table-wrap" hx-swap="innerHTML" hx-indicator="#admin-search-indicator" hx-push-url="true">Publié<?= $sortArrow('is_published') ?></a></th>
             <th scope="col">Accès</th>
             <th scope="col">Actions</th>
         </tr>
@@ -64,7 +68,7 @@ $sortArrow = function(string $col) use ($sortCol, $sortDir): string {
             <td><input type="checkbox" name="selected_theses[]" value="<?= $thesis['id'] ?>"></td>
             <td class="admin-table-id"><?= htmlspecialchars($thesis['identifier'] ?? $thesis['id']) ?></td>
             <td>
-                <div class="thesis-title"><?= htmlspecialchars($thesis['title']) ?></div>
+                <div class="thesis-title" title="<?= htmlspecialchars($thesis['title']) ?>"><?= htmlspecialchars($thesis['title']) ?></div>
             </td>
             <td><?= htmlspecialchars($thesis['authors'] ?? 'N/A') ?></td>
             <td><?= $thesis['year'] ?></td>