fix: mark languages as required, add required-field visual indicators on both forms

- checkbox-list.php: support $required prop → adds required + aria-required on fieldset
- add.php: languages checkbox now marked required (matches server-side validation)
- partage/index.php: same for student form
- admin.css: dashed border on required inputs, bold labels, red asterisk via :has(), "Champs obligatoires" note
- Both forms now show "* Champs obligatoires" note at top

Server-side required fields = titre, auteurice, synopsis, année, orientation, ap, finality, languages (≥1), access_type_id, confirmation_email. All now have required attribute + visual asterisk.

app/public/admin/add.php

@@ -59,6 +59,7 @@ include APP_ROOT . '/templates/header.php';
 
 
 
+    <p class="required-note"><span class="asterisk">*</span> Champs obligatoires</p>
     <form action="actions/formulaire.php" method="post" enctype="multipart/form-data" class="admin-form">
         <input type="hidden" name="csrf_token" value="<?= htmlspecialchars($_SESSION["csrf_token"]) ?>">
 
@@ -107,7 +108,7 @@ include APP_ROOT . '/templates/header.php';
             <?php $name = 'ap';          $label = 'Atelier pluridisciplinaire :'; $options = $apPrograms;    $selected = $formData['ap'] ?? '';            $required = true; $placeholder = ''; $attrs = withAutofocus('ap');          include APP_ROOT . '/templates/partials/form/select-field.php'; ?>
             <?php $name = 'finality';   $label = 'Finalité du master :';       $options = $finalityTypes;   $selected = $formData['finality'] ?? '';    $required = true; $placeholder = ''; $attrs = withAutofocus('finality');    include APP_ROOT . '/templates/partials/form/select-field.php'; ?>
 
-            <?php $name = 'languages'; $label = 'Langue(s) :'; $options = $languages; $checked = $formData['languages'] ?? []; include APP_ROOT . '/templates/partials/form/checkbox-list.php'; ?>
+            <?php $name = 'languages'; $label = 'Langue(s) :'; $options = $languages; $checked = $formData['languages'] ?? []; $required = true; include APP_ROOT . '/templates/partials/form/checkbox-list.php'; ?>
             <?php $name = 'formats';   $label = 'Format(s) :'; $options = $formatTypes; $checked = $formData['formats'] ?? [];   include APP_ROOT . '/templates/partials/form/checkbox-list.php'; ?>
 
             <?php $name = 'tag'; $label = 'Mots-clés :'; $value = old('tag'); $placeholder = 'sociologie, anthropologie, ...'; $hint = 'Séparez par des virgules. Max 10 mots-clés.'; $attrs = withAutofocus('tag'); include APP_ROOT . '/templates/partials/form/text-field.php'; ?>

app/public/assets/css/README.md

@@ -1,21 +0,0 @@
-# CSS Architecture
-
-## File Structure
-
-- **variables.css** — all CSS custom properties (single source of truth for every color/token)
-- **common.css** — reset, header/nav, search bar, accessibility utilities (loaded on all pages)
-- **main.css** — home page
-- **search.css** — search/directory page
-- **tfe.css** — individual thesis page
-- **apropos.css** — about + licence pages
-- **system.css** — admin system dashboard
-- **admin.css** — admin section (loaded alongside `common.css` on every admin page)
-- **modern-normalize.min.css** — third-party reset (minified, do not edit)
-
-## Rules
-
-- Every color value lives in `variables.css` as a CSS custom property.
-- No hardcoded hex, rgb(), or rgba() in any other file.
-- All files `@import url("./variables.css")` at the top.
-- Admin and public share the same token names — no separate admin theme.
-- No dark-mode media query. System page uses the same light tokens as the rest of the admin section.

app/public/assets/css/admin.css

@@ -147,6 +147,43 @@
     padding-right: 1.2rem;
 }
 
+/* Required-field indicator */
+.admin-form
+    input:not([type="checkbox"]):not([type="radio"]):not([type="file"]):not(
+        [type="hidden"]
+    ):not([type="submit"]):required,
+.admin-form select:required,
+.admin-form textarea:required {
+    border-bottom-style: dashed;
+}
+
+.admin-form
+    div:has(
+        input:required:not([type="checkbox"]):not([type="radio"]):not([type="file"]):not([type="hidden"])) > label,
+.admin-form div:has(select:required) > label,
+.admin-form div:has(textarea:required) > label {
+    font-weight: 600;
+}
+
+/* Required-field indicator (student form / generic labels) */
+label:has(+ input:required:not([type="hidden"]))::after,
+label:has(+ select:required)::after,
+label:has(+ textarea:required)::after,
+label:has(+ div > input:required)::after {
+    content: " *";
+    color: var(--error, #c00);
+}
+
+/* Visually-hidden "required fields marked with *" note */
+.required-note {
+    font-size: var(--step--2);
+    color: var(--text-secondary);
+    margin-bottom: var(--space-xs);
+}
+.required-note .asterisk {
+    color: var(--error, #c00);
+}
+
 /* File inputs */
 .admin-file-input {
     display: flex;

app/public/partage/index.php

@@ -308,6 +308,7 @@ function renderShareLinkForm(string $slug, array $link): void
             <div class="flash-success" role="alert"><?= htmlspecialchars($flashSuccess) ?></div>
             <?php endif; ?>
 
+            <p class="required-note"><span class="asterisk">*</span> Champs obligatoires</p>
             <form action="/partage/<?= urlencode($slug) ?>/submit" method="post" enctype="multipart/form-data" class="admin-form">
                 <input type="hidden" name="share_link_token" value="<?= htmlspecialchars($shareCsrfToken) ?>">
 
@@ -376,7 +377,7 @@ function renderShareLinkForm(string $slug, array $link): void
                     <?php $name = 'ap'; $label = 'Atelier pluridisciplinaire :'; $options = $apPrograms; $selected = isset($formData['ap']) ? $formData['ap'] : ''; $required = true; $placeholder = ''; include APP_ROOT . '/templates/partials/form/select-field.php'; ?>
                     <?php $name = 'finality'; $label = 'Finalité du master :'; $options = $finalityTypes; $selected = isset($formData['finality']) ? $formData['finality'] : ''; $required = true; $placeholder = ''; include APP_ROOT . '/templates/partials/form/select-field.php'; ?>
 
-                    <?php $name = 'languages'; $label = 'Langue(s) :'; $options = $languages; $checked = $formData['languages'] ?? []; include APP_ROOT . '/templates/partials/form/checkbox-list.php'; ?>
+                    <?php $name = 'languages'; $label = 'Langue(s) :'; $options = $languages; $checked = $formData['languages'] ?? []; $required = true; include APP_ROOT . '/templates/partials/form/checkbox-list.php'; ?>
                     <?php $name = 'formats'; $label = 'Format(s) :'; $options = $formatTypes; $checked = $formData['formats'] ?? []; include APP_ROOT . '/templates/partials/form/checkbox-list.php'; ?>
 
                     <?php $name = 'tag'; $label = 'Mots-clés :'; $value = old($formData, 'tag'); $placeholder = 'sociologie, anthropologie, ...'; $hint = 'Séparez par des virgules. Max 10 mots-clés.'; include APP_ROOT . '/templates/partials/form/text-field.php'; ?>

app/templates/partials/form/checkbox-list.php

@@ -12,13 +12,15 @@
  *   string  $label     — group label text
  *   array   $options   — each element must have 'id' and 'name' keys
  *   array   $checked   — array of 'id' values that are currently checked
+ *   bool    $required  — whether at least one checkbox must be checked; default false
  */
 
-$checked = $checked ?? [];
+$checked  = $checked  ?? [];
+$required = $required ?? false;
 ?>
 <div>
     <span class="admin-row-label"><?= htmlspecialchars($label) ?></span>
-    <fieldset class="admin-checkbox-group">
+    <fieldset class="admin-checkbox-group"<?= $required ? ' required aria-required="true"' : '' ?>>
         <legend class="sr-only"><?= htmlspecialchars($label) ?></legend>
         <ul>
             <?php foreach ($options as $opt): ?>