feat(action): site + example publish

[nobkd]

This is still very much WIP, and completely untested.
I'll try working more on this, sometime next week.

[nobkd]

Note: I changed the archive name to source.tar.gz instead of using <dirname>.tar.gz. Currently the action generates both versions for compatibility.

I can also undo the change, to keep using the dir name variant. It doesn't really matter, but having the same file name for each example would be more expected I think.

Even after merging this, it is a change of one word (see create.js), so we can change it back before the next release, if we change our mind.