docs: api docs for new feature in client

[wkillerud]

Relates to podium-lib/client#395

[wkillerud]

Maybe we ought to do the same for Podium as I did with Metrics JS. Move all contents from package's READMEs to the docsite and link to it:

https://github.com/metrics-js/client?tab=readme-ov-file#metricsclient

[digitalsadhu]

Maybe we ought to do the same for Podium as I did with Metrics JS. Move all contents from package's READMEs to the docsite and link to it:

https://github.com/metrics-js/client?tab=readme-ov-file#metricsclient

I guess the concern might be that when docs are not co-located, it's easy to forget them. In practice, I've forgotten to do the docs even when they are co-located. So.. I'm open to either approach.

[wkillerud]

The way we have it set up now we have two places we can forget to update 😄 But yeah, co-location is nice. No rush to do anything, just throwing it out there.