Github action?

It would be cool to have something that was a bit like the standard Github caching action.

It wouldn't be very sophisticated I expect, just something that triggers a save/restore in the right places and has some parameters for setting up the storage location, but it would still look a bit cleaner from a user perspective.

The issue names no files, tests, or entry points. Start by reviewing the existing cache save/restore behavior and how the project integrates with GitHub Actions. Done would mean a documented, usable action with configurable storage and correctly timed save/restore operations.

Written by the indexing model from the issue text.