Generate docs PR's for holes suggested by skills in this repo

For the pinvoke skill, we had an agent look for material there (which we believe is authoritatively reviewed) that was missing from the docs. It found 7 things, which are now fixed. We should do this over all the skills in here, possibly regularly. Not just will this help customers reading the docs, but more interestingly should help future models need the skills less.

Begin with the pinvoke skill and compare its authoritatively reviewed material with the existing docs, then repeat that review across the other skills. Done means the identified documentation gaps are addressed through docs PRs, with a repeatable approach if this is run regularly.

Written by the indexing model from the issue text.