Well, it's one thing you can create with https://hofstadter.io/docs
I bought one on Webflow, but have since moved off their platform to Hugo, which has themes (same idea) and where some are paid too
I don't call out "living boilerplate" as a section in the documentation, but I think setting up a generator module with just static files should suffice. Certainly you can get more fancy if you want your users to provide some inputs.
Happy to help or show you this in Slack or a video call.
I'm planning a *create" subcommand to make this even easier for those who would use your boilerplate. It will have an interactive first time experience like react create-app