precompress static pages as brotli

[skyfaller]

One possible compression program:
https://github.com/neosmart/static-compress

Use precompressed directive for Caddy to check for the existence of precompressed files:
https://caddyserver.com/docs/caddyfile/directives/file_server

It'll be easy enough to run the first time. The question is, how do we make sure to re-compress only the files that have changed on a static website? Maybe run https://github.com/kurtbuilds/checkexec

How do we install these unusual programs?