Add action for undo of previous X moves

[kinabalu]

No description provided.

[pastudan]

This would be cool if it automatically rolled back your previous move(s) when they are the opposite direction. For example ➡️⬇️➡️ and then ⬅️⬆⬅ would completely undo your move history and net you 0 moves

[pastudan]

This is a start, but I found one issue with it that I'm not sure how to fix:
https://github.com/mysticcoders/mysticrobots/compare/undo-history?expand=1

For example, when you down from here, then right, then left, it removes the right move from the history and doesn't record the left. What should really happen is that the right move should be removed and the left should be recorded.

[kinabalu]

I'd like to work toward getting some tests added sooner rather than later, jest, and @testing-library are my preferences.

if we can pull out the move functionality and write some tests covering the cases, we'd be better positioned to make changes faster. thoughts? we can open another ticket to track this project and tackle it