OK, I have a project folder, with /src and /public.
The project folder has a git repo and a /src folder. It also has a /public folder that has its own git repo. The project folder's .gitignore includes /public. So the project folder will have a different github repo than the actual github pages.
So I can work on the /src code, send it through Gulp to transpile and minify and put in /public, then commit and push it to the "src" repo, then commit and push the /public to my github pages separately.
The editor only needs the project folder. But I'll need 2 terminals, one for each repo.
'gh-pages' is cool, but that won't work for this as far as I can tell.
I was originally doing this with Webpack, but was running into FOUC problems. Doing it without the Webpack bundling and using Gulp to run tasks works better for this.