Add npm package for npx @tsiry/fin distribution
Publishable scoped npm package that fetches the matching prebuilt binary
from the GitHub release (SHA-256 verified) on install, so users can run
`npx @tsiry/fin` or `npm install -g @tsiry/fin`.
Supports darwin/linux/freebsd/netbsd (x64, arm64) and openbsd (x64).