That would be discourse_theme new 
@grubba how would you feel about rolling this into core as a rake task? Like
bin/rake plugin:create
People need to have a working core dev environment to work on plugins anyway, so it seems like a good fit? It would also make more ‘official’, and easier for the whole team to maintain.
I wonder if it would be better to make it 100% git, instead of relying on people using github (and having the gh cli)? Some people use other services to host their plugins, and also may not want them to immediately be made public.
In discourse_theme we maintain a local cache of the theme-skeleton, so it even works offline!