That said, I'm not sure how much much of ActivityPub you could make use of for a static site? You could definitely publish an Actor and create an Outbox listing your content. You could also have deploy triggers to notify followers when you publish...
But how does someone follow you? In order for that to work, there needs to be a server to accept a Follow activity and add them to the Followers collection to be notified on publication.
ActivityPub by definition doesn't work with a static site. But check out this project which offloads the ActivityPub parts for any site assuming you can make a request there as part of your static site build process https://fed.brid.gy/