meta: publish interface packages when available
meta: publish interface packages when available

Adds a workflow that, on every push to master, will publish new versions
of interface subpackages to the NPM registry if any are available.

Staged to trigger on a test branch for now.

urbit/urbit,urbit/urbit,ngzax/urbit,urbit/urbit,ngzax/urbit,urbit/urbit,urbit/urbit,urbit/urbit,ngzax/urbit,ngzax/urbit,ngzax/urbit,ngzax/urbit,urbit/urbit,ngzax/urbit