claat watch

[vorburger]

It would be cool if there was a claat watch kind of command.

I would expect it to behave just like export, followed by serve - but then keep "watching" (inotify) the input files for changes, and automagically re-run export at every change.

This would make for a "tight inner loop" while writing Codelabs, allowing to change a Markdown file, Ctrl-S to Save it, F5 to reload in the brower.

It is, of course, possible to put something like this together manually, using e.g. like https://github.com/eradman/entr (also on https://eradman.com/entrproject/) or some other tool like that; as I have started (and may finish) on #873, but a "native" solution built into claat one day could be neat.