Drop custom fields from elements/* failure responses

Resolves #11807

Author: brandonkelly

CHANGELOG.md

@@ -11,6 +11,7 @@
 - Improved the console output for the `gc` command.
 - The `gc` command now runs garbage collection for data caches.
 - Exception JSON responses now include `name` and `code` keys. ([#11799](https://github.com/craftcms/cms/discussions/11799))
+- `elements/*` actions no longer include custom field values in the failure response data, improving performance. ([#11807](https://github.com/craftcms/cms/discussions/11807))
 
 ### Fixed
 - Fixed a bug where keyboard focus wasn’t being maintained when changing the element type within a “Related To” condition rule.

src/controllers/ElementsController.php

@@ -1735,7 +1735,12 @@ private function _asSuccess(string $message, ElementInterface $element, array $d
 
     private function _asFailure(ElementInterface $element, string $message): ?Response
     {
-        /** @var Element $element */
-        return $this->asModelFailure($element, $message, 'element');
+        $data = [
+            'modelName' => 'element',
+            'element' => $element->toArray($element->attributes()),
+            'errors' => $element->getErrors(),
+        ];
+
+        return $this->asFailure($message, $data, ['element' => $element]);
     }
 }