fix(planka): propagation erreurs Planka + noms étiquettes + position dans saveCard

- update_card: transmet position à Planka + retourne erreur réelle si Planka rejette
- saveCard: n'envoie listId que si changé (position requise par Planka), sinon nom/desc/dueDate seul
- Labels: affiche le nom en texte dans le badge coloré (comme Planka)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

modules/planka/api.php

@@ -127,12 +127,14 @@ if ($action === 'update_card') {
     $id = $_GET['id'] ?? null; if (!$id) tErr('ID manquant');
     $d = tBody();
     $payload = [];
-    if (isset($d['name']))        $payload['name']        = $d['name'];
-    if (isset($d['description']))  $payload['description']  = $d['description'];
-    if (array_key_exists('dueDate', $d)) $payload['dueDate'] = $d['dueDate'];
-    if (isset($d['listId']))       $payload['listId']       = $d['listId'];
+    if (isset($d['name']))               $payload['name']        = $d['name'];
+    if (isset($d['description']))        $payload['description'] = $d['description'];
+    if (array_key_exists('dueDate', $d)) $payload['dueDate']     = $d['dueDate'];
+    if (isset($d['listId']))             $payload['listId']      = $d['listId'];
+    if (isset($d['position']))           $payload['position']    = (float)$d['position'];
     $resp = planka_api('PATCH', '/api/cards/' . $id, $payload, $token);
-    tOk($resp['item'] ?? []);
+    if (empty($resp['item'])) tErr($resp['message'] ?? ($resp['problems'][0] ?? 'Planka a rejeté la mise à jour'), 502);
+    tOk($resp['item']);
 }
 
 if ($action === 'delete_card') {

modules/planka/assets/planka.css

@@ -166,10 +166,22 @@
 }
 
 .pk-label {
+  display: inline-flex;
+  align-items: center;
+  height: 20px;
+  padding: 0 8px;
+  border-radius: 4px;
+  font-size: .72rem;
+  font-weight: 600;
+  color: #fff;
+  white-space: nowrap;
+  text-shadow: 0 1px 2px rgba(0,0,0,.3);
+  min-width: 36px;
+}
+.pk-label:empty {
   height: 6px;
   width: 36px;
-  border-radius: 3px;
-  display: inline-block;
+  padding: 0;
 }
 
 .pk-card-name {