style: give PostGuard::postType() its docblock back (re-review N-1)

unavailableType() moves below postType(), so the docblock on postType()'s
return type sits on postType() again.

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

src/Integrations/WordPress/PostGuard.php

@@ -136,15 +136,6 @@ final class PostGuard
      * so a plain `object` return type is accurate and still lets callers branch with
      * `is_wp_error()` / `instanceof WP_Error`, exactly like editable() above.
      */
-    /** The answer for a post type that is not available to the tools – the same for unknown and excluded ones. */
-    public static function unavailableType(string $name): WP_Error
-    {
-        return Errors::notFound(
-            sprintf('Inhaltstyp "%s" ist nicht verfügbar.', $name),
-            'Verfügbare Inhaltstypen über lit/content-types (direkt: lit-content-types) abrufen.'
-        );
-    }
-
     public static function postType(mixed $postType, ContentSchema $schema, string $cap): object
     {
         $name = is_string($postType) ? $postType : '';
@@ -161,6 +152,15 @@ final class PostGuard
         return $object;
     }
 
+    /** The answer for a post type that is not available to the tools – the same for unknown and excluded ones. */
+    public static function unavailableType(string $name): WP_Error
+    {
+        return Errors::notFound(
+            sprintf('Inhaltstyp "%s" ist nicht verfügbar.', $name),
+            'Verfügbare Inhaltstypen über lit/content-types (direkt: lit-content-types) abrufen.'
+        );
+    }
+
     /**
      * Whether a list/search query for this post type must stay restricted to the current
      * user's own entries because they lack edit_others_posts. Filtering per row after the