fix: content-create names the Divi layout when its write fails (S50)

A failing Divi layout write discarded the draft with the fields/terms
message (REASON_EXTRAS); it now passes NewDraft::REASON_LAYOUT (ledger T9).

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01At3V6SjwbMe6eMzVGW3Hs7

src/Integrations/WordPress/Content/ContentCreateAbility.php

@@ -144,7 +144,7 @@ final class ContentCreateAbility implements Ability
         try {
             $layout = $withDivi ? $this->divi?->write($postId, $postType, self::sections($input)) : null;
         } catch (Throwable $e) {
-            $draft->discard($postId, $e, NewDraft::REASON_EXTRAS);
+            $draft->discard($postId, $e, NewDraft::REASON_LAYOUT);
         }
         if ($layout instanceof WP_Error) {
             return $draft->refuse($postId, $layout);

src/Integrations/WordPress/Content/NewDraft.php

@@ -26,6 +26,7 @@ final class NewDraft
 {
     public const REASON_INSERT = 'WordPress hat beim Anlegen des Eintrags einen Fehler gemeldet.';
     public const REASON_EXTRAS = 'Felder, Begriffe oder Beitragsbild konnten nicht gespeichert werden.';
+    public const REASON_LAYOUT = 'Das Divi-Layout konnte nicht gespeichert werden.';
 
     public function __construct(
         private PostWriter $writer,