:four: Fix identification of "primary maintainers"

[mpadge]

From @zkamvar via #64:

I noticed a couple of things as a maintainer/former maintainer/contributing author of four of the highlighted packages in ropensci-review-tools.github.io/repometrics-demo

My question is: What does it mean to be a "primary maintainer"?

For the sandpaper dashboard, the author metrics seem to be not quite right about the "primary maintainers"

My maintainer status was removed last year
froggleston is listed as the current maintainer
the most recent release was in August 2025 (though I understand that for this demo, there likely was a delay)