Add Mots-clés and Langues management to contenus page

- Add searchLanguages, getAllLanguagesWithCount, renameLanguage, mergeLanguage, deleteLanguage to Database
- Create actions/language.php handler with rename/merge/merge_bulk/delete actions
- Add merge_bulk action to actions/tag.php
- Add Mots-clés section to contenus template with HTMX search, select checkboxes, rename/delete/merge buttons, and multi-select merge toolbar
- Add Langues section to contenus template with same pattern
- Create contenus-tags-fragment.php and contenus-languages-fragment.php HTMX fragments
- Remove form-settings- from flat-fieldset CSS selector so fieldsets in contenus retain border/padding
- contenus.php: add 'Gérer les mots-clés' link to /admin/tags.php
- contenus.php: add Langues fieldset with HTMX search + table (rename/merge/delete/bulk)
- tags.php: add HTMX search bar, checkbox column, bulk merge toolbar
- Create tags-fragment.php and contenus-langues-fragment.php for HTMX
- Remove tab component and associated CSS
- Simplify JS: separate tags/langues-prefixed functions
- Fix redirects: tag.php defaults to /admin/tags.php, supports return override
- Keep tags.php standalone page and Mots-clés button unchanged

app/templates/admin/contenus.php

@@ -1,3 +1,5 @@
+<div class="admin-with-toc">
+<?php include APP_ROOT . '/templates/admin/partials/admin-toc.php'; ?>
 <main id="main-content">
     <h1>Contenus</h1>
 
@@ -44,6 +46,35 @@
     </table>
     </section>
 
+    <!-- ═══════════════════════════════════════════════════════════════════
+         DONNÉES SECONDAIRES
+         ═══════════════════════════════════════════════════════════════════ -->
+    <section aria-labelledby="donnees-secondaires-title">
+        <h2 id="donnees-secondaires-title">Données Secondaires</h2>
+
+        <!-- ── Mots-clés ── -->
+        <p><a href="/admin/tags.php" class="btn btn--sm btn--primary">Gérer les mots-clés</a></p>
+
+        <!-- ── Langues ── -->
+        <fieldset>
+            <legend>Langues</legend>
+
+            <form id="langues-search-form"
+                  hx-get="/admin/contenus-langues-fragment.php"
+                  hx-target="#langues-table-wrap"
+                  hx-swap="innerHTML"
+                  hx-trigger="input changed delay:200ms from:input[name=q], keyup[key=='Enter'] from:input[name=q]"
+                  hx-push-url="false"
+                  style="margin-bottom:var(--space-xs)">
+                <input type="text" name="q" placeholder="Rechercher une langue…" style="max-width:300px">
+            </form>
+
+            <div id="langues-table-wrap" hx-get="/admin/contenus-langues-fragment.php" hx-trigger="load" hx-swap="innerHTML">
+                <!-- populated by HTMX -->
+            </div>
+        </fieldset>
+    </section>
+
     <!-- ═══════════════════════════════════════════════════════════════════
          PARAMÈTRES DU FORMULAIRE
          ═══════════════════════════════════════════════════════════════════ -->
@@ -163,44 +194,22 @@
     <?php
     $blocks = $formHelpBlocks;
 
-    // ── Student form structure — each help block above its fieldset ───────────
-    // Pairs: [help_key, fieldset_name, fieldset_inputs]
     $pairs = [
-        // Top of form
         ['partage_intro',        null, null],
-
-        // Informations du TFE
         ['fieldset_tfe_info',    'Informations du TFE',
             ['Titre', 'Sous-titre', 'Auteur·ice(s)', 'Contact visible', 'Synopsis']],
-
-        // Langue(s)
         ['fieldset_languages',   'Langue(s)',
             ['Langues du TFE (cases à cocher)', 'Autre(s) langue(s)']],
-
-        // Mots-clés
         ['fieldset_keywords',    'Mots-clés',
             ['Mots-clés (max 10), séparés par des virgules']],
-
-        // Cadre académique
         ['fieldset_academic',    'Cadre académique',
             ['Année', 'Orientation', 'AP', 'Finalité']],
-
-        // Composition du jury
         ['fieldset_jury',        'Composition du jury',
             ['Président·e', 'Promoteur·ice(s)', 'Lecteur·ices']],
-
-        // Format(s) + Fichiers
         ['fieldset_files',       'Format(s) + Fichiers',
             ['Formats (PDF, vidéo, audio, site web…)', 'Couverture', 'Note d\'intention', 'Fichier principal', 'Annexes']],
-
-        // Métadonnées complémentaires (supprimé)
-        // Ces champs sont redondants avec les fichiers attachés
-
-        // Degrés d'ouverture et licences
         ['fieldset_access',      'Degrés d\'ouverture et licences',
             ['Généralités', 'Degré (libre/interne/interdit)', 'Licence', 'CC2r']],
-
-        // E-mail de confirmation
         ['fieldset_email',       'E-mail de confirmation',
             ['Adresse e-mail']],
     ];
@@ -208,7 +217,6 @@
 
     <div class="fhb-structure">
         <?php foreach ($pairs as [$helpKey, $fieldsetName, $inputs]):
-            // Help block
             $b     = $blocks[$helpKey] ?? ['content' => '', 'name' => '', 'enabled' => 0];
             $title = $b['name'] ?: ($fieldsetName ?? $helpKey);
         ?>
@@ -239,6 +247,131 @@
     </section>
 
 </main>
+</div>
+
+<!-- ══════════════════════════════════════════════════════════════
+     CONFIRM DIALOGS FOR LANGUES
+══════════════════════════════════════════════════════════════ -->
+
+<dialog id="langues-merge-dialog" class="admin-dialog admin-dialog--sm" aria-labelledby="langues-merge-title">
+    <div class="admin-dialog__header">
+        <h2 id="langues-merge-title">Fusionner la langue</h2>
+        <button type="button" class="admin-dialog__close" aria-label="Fermer"
+                onclick="this.closest('dialog').close()">&#x2715;</button>
+    </div>
+    <div class="admin-dialog__alert">
+        <p>Fusionner dans « <strong id="langues-merge-target-name"></strong> » ? La langue source sera supprimée.</p>
+    </div>
+    <div class="admin-dialog__footer">
+        <button type="button" class="btn btn--warning" onclick="this.closest('dialog').close(); languesSubmitPending()">Fusionner</button>
+        <button type="button" class="btn btn--secondary" onclick="this.closest('dialog').close()">Annuler</button>
+    </div>
+</dialog>
+
+<dialog id="langues-delete-dialog" class="admin-dialog admin-dialog--sm" aria-labelledby="langues-delete-title">
+    <div class="admin-dialog__header">
+        <h2 id="langues-delete-title">Supprimer la langue</h2>
+        <button type="button" class="admin-dialog__close" aria-label="Fermer"
+                onclick="this.closest('dialog').close()">&#x2715;</button>
+    </div>
+    <div class="admin-dialog__alert">
+        <p>Supprimer « <strong id="langues-delete-name"></strong> » ? Cette action est irréversible.</p>
+    </div>
+    <div class="admin-dialog__footer">
+        <button type="button" class="btn btn--danger" onclick="this.closest('dialog').close(); languesSubmitPending()">Supprimer</button>
+        <button type="button" class="btn btn--secondary" onclick="this.closest('dialog').close()">Annuler</button>
+    </div>
+</dialog>
+
+<dialog id="langues-bulk-merge-dialog" class="admin-dialog admin-dialog--sm" aria-labelledby="langues-bulk-merge-title">
+    <div class="admin-dialog__header">
+        <h2 id="langues-bulk-merge-title">Fusionner des langues</h2>
+        <button type="button" class="admin-dialog__close" aria-label="Fermer"
+                onclick="this.closest('dialog').close()">&#x2715;</button>
+    </div>
+    <div class="admin-dialog__alert">
+        <p>Fusionner <strong><span id="langues-bulk-merge-count"></span> langue(s)</strong> sélectionnée(s) dans :</p>
+        <select id="langues-bulk-merge-target-select" class="admin-select--inline" style="margin-top:var(--space-xs); width:100%" required>
+            <option value="">— Choisir la destination —</option>
+        </select>
+    </div>
+    <div class="admin-dialog__footer">
+        <button type="button" class="btn btn--warning" onclick="languesExecBulkMerge()">Fusionner</button>
+        <button type="button" class="btn btn--secondary" onclick="this.closest('dialog').close()">Annuler</button>
+    </div>
+</dialog>
+
+<script>
+let _languesPendingForm = null;
+
+function languesConfirmMerge(btn) {
+    const form = btn.closest('form');
+    const select = form.querySelector('select[name="target_id"]');
+    if (!select.value) return true;
+    _languesPendingForm = form;
+    document.getElementById('langues-merge-target-name').textContent = select.options[select.selectedIndex]?.text ?? '';
+    document.getElementById('langues-merge-dialog').showModal();
+    return false;
+}
+
+function languesConfirmDelete(btn, name) {
+    _languesPendingForm = btn.closest('form');
+    document.getElementById('langues-delete-name').textContent = name;
+    document.getElementById('langues-delete-dialog').showModal();
+}
+
+function languesSubmitPending() {
+    if (_languesPendingForm) _languesPendingForm.submit();
+}
+
+function languesToggleAll(src) {
+    document.querySelectorAll('input[name="selected_langs[]"]').forEach(cb => cb.checked = src.checked);
+    languesUpdateBulk();
+}
+
+function languesUpdateBulk() {
+    const n = document.querySelectorAll('input[name="selected_langs[]"]:checked').length;
+    document.getElementById('langues-selected-count').textContent = n;
+    document.getElementById('langues-bulk-actions').style.display = n > 1 ? 'flex' : 'none';
+}
+
+function languesConfirmBulkMerge() {
+    const checked = document.querySelectorAll('input[name="selected_langs[]"]:checked');
+    if (checked.length < 2) return;
+    document.getElementById('langues-bulk-merge-count').textContent = checked.length;
+    const sel = document.getElementById('langues-bulk-merge-target-select');
+    sel.innerHTML = '<option value="">— Choisir la destination —</option>';
+    checked.forEach(cb => {
+        const tr = cb.closest('tr');
+        sel.innerHTML += '<option value="' + cb.value + '">' + tr.querySelector('td:nth-child(2)').textContent.trim() + '</option>';
+    });
+    document.getElementById('langues-bulk-merge-dialog').showModal();
+}
+
+function languesExecBulkMerge() {
+    const targetId = document.getElementById('langues-bulk-merge-target-select').value;
+    if (!targetId) return;
+    document.getElementById('langues-bulk-target').value = targetId;
+    const container = document.getElementById('langues-bulk-checkboxes');
+    container.innerHTML = '';
+    document.querySelectorAll('input[name="selected_langs[]"]:checked').forEach(cb => {
+        const inp = document.createElement('input');
+        inp.type = 'hidden';
+        inp.name = 'selected_langs[]';
+        inp.value = cb.value;
+        container.appendChild(inp);
+    });
+    document.getElementById('langues-bulk-merge-dialog').close();
+    document.getElementById('langues-bulk-form').submit();
+}
+
+document.addEventListener('htmx:afterSwap', function(evt) {
+    if (evt.target.id === 'langues-table-wrap') {
+        document.querySelectorAll('input[name="selected_langs[]"]').forEach(cb => cb.addEventListener('change', languesUpdateBulk));
+        languesUpdateBulk();
+    }
+});
+</script>
 
 <script>
 (function () {