ADA - Container element is empty

Some roles are designed to contain other roles. This element has this type of role, but it doesn't contain any [required-owned elements](https://www.w3.org/TR/wai-aria-1.1/#mustContain).

<img width="862" height="288" alt="Image" src="https://github.com/user-attachments/assets/5070fade-2f67-4a92-8660-60624b440c52" />