document data

[focardozom]

Potential fix for #1681. Here’s a summary of the relevant points discussed in the issue:

1. Existing Tools: The sinew package provides functions for documenting, but its workflow might overlap with usethis. More details can be found in the workflow guide.

2. Alternative Solution: Another approach is proposed here, which handles various R objects and offers customizable documentation. However, it may require style translation and simplification to make it more accessible.

3. This Pull Request: The use_document_data function is simpler and easier to read, though it doesn’t offer the same level of customization as the alternative.

[jennybc]

This isn't a full review, but I came by quickly to see if this pkgdown failure is related to one seen in a different PR. It doesn't seem to be.

The pkgdown CI failure appears to be real because the new functions need to be added to the reference index. So that would be good to fix up to make this PR complete.