A template for `jsdoc` that generat the HTML5 public classref.
The script can be run via `npm run docs` to print to stdout.
You can dry run via `npm run docs -- --d dry-run` or write to file via
`npm run docs -- -d /path/to/file.rst`
Also update Makefile in `doc/` and add dry run test to CI.
(cherry picked from commit 472482013e)
