meta: setup monorepo

[ignatiusmb]

Prerequisite to #207

[benmccann]

not sure if you want to try to follow how we have svelte and kit setup, but we have packages and sites directories in those projects

[ignatiusmb]

I'd want to, though I kind of see packages as npm modules and we don't publish any of them here, and I don't see how there would ever be more than 1 directory in sites. I'm open to alternatives for a dirname that could consolidate the app and website under one place to make the root dir less crowded.