Still working on import tree today. I decided to make the imported commit be on an unrelated history from the main branch, which avoids some very susprising merge behavior, but means users will need to pass --allow-unrelated-histories to git merge.

Also got export and sync commands updating the remote tracking branch. It was surprisingly complicated to do.

With that done, I've tested exporting to a directory remote, then making changes to the directory manually, and importing, and it all works together.