mod_rest: Strip down error payloads to avoid stack overflow When the util.error feature of including a traceback in the error, util.json can't serialize it as it is often self-referential.

<tr>
  <td colspan="2">
    <script src="https://hcaptcha.com/1/api.js" async defer></script>
    <div class="h-captcha" data-sitekey="{captcha_public_key}"></div>
  </td>
</tr>