Feature Request: Provide TL_WRAPPERS information

[delude88]

I'm currently using the Contao Content API to connect React / Next.js with Contao.
Currently I'm stuck on realizing wrapper elements, since no additional information about the wrapper state is delivered through the cte response.
So it would be nice to have the TL_WRAPPERS information (start, stop, etc.) regarding each cte inside the page response.

It may be possible by customizing the request using the provided hook, but this information might be common for many use cases.