Add CI for publishing package to npm

[mkozakov]

Add a CI workflow for posting packages to NPM.

[kravse]

Since we auto publish now when main changes, I wonder if we should block pushing directly to main with something like:

git config branch.main.pushRemote no_push

Hmm maybe I'm wrong. https://stackoverflow.com/a/54239368

[mkozakov]

@kravse we have main branch protection on github level