This exists: it's the git-annex assistant! You just have to configure the "annex.largefiles", because by default git-annex doesn't actually commit the content of the files, since it's designed to handle large binary files.

But if you set that option and run the Assistant, it'll auto-commit files when they change, and can even auto-sync them with other computers, cloud storage, Android devices, etc.

https://git-annex.branchable.com/assistant/