fieldset-academic: dim locked year field, remove required asterisk

When locked_year is set, render the Année label+input inline with
opacity:0.55 instead of via text-field.php. No asterisk since editing
is disabled. The hidden input still ensures the value is submitted.

app/templates/partials/form/fieldset-academic.php

@@ -22,24 +22,29 @@ $lockedYear      = $lockedYear      ?? null;
 
     <?php
     $name = 'année'; $label = 'Année :';
-    $required = !$adminMode;
     $type = 'number';
     $placeholder = date('Y');
-    $attrs = $withAutofocusFn('année', ['min' => 2000, 'max' => date('Y') + 1]);
 
     if ($lockedYear !== null):
-        // Link specifies a locked academic year: pre-fill, disable editing.
-        $value = (string)$lockedYear;
-        $attrs['disabled'] = true;
-        $attrs['readonly'] = true;
-        // Include a hidden input so the value is still submitted when the field is disabled.
+        // Link specifies a locked academic year: render a dimmed, non-editable
+        // field with no required indicator, plus a hidden input for submission.
         ?>
         <input type="hidden" name="année" value="<?= htmlspecialchars((string)$lockedYear) ?>">
+        <div style="opacity:0.55">
+            <label for="année"><?= htmlspecialchars($label) ?></label>
+            <input type="number" id="année"
+                   value="<?= htmlspecialchars((string)$lockedYear) ?>"
+                   disabled readonly
+                   min="2000" max="<?= date('Y') + 1 ?>"
+                   placeholder="<?= htmlspecialchars($placeholder) ?>">
+        </div>
         <?php
     else:
+        $required = !$adminMode;
         $value = $oldFn('année');
+        $attrs = $withAutofocusFn('année', ['min' => 2000, 'max' => date('Y') + 1]);
+        include APP_ROOT . '/templates/partials/form/text-field.php';
     endif;
-    include APP_ROOT . '/templates/partials/form/text-field.php';
     ?>
 
     <?php