Client side move generation leads to weird reconciliation animations

[kreibaum]

If you move fast, then the server can send a previous state, leading to a repeat animation.

I think the following happens:

Client sends A Client sends B (possible with client side move generation) Server sends original state + A Clients rolls back Server sends original + A + B Client goes back to that state.

But we still want Rollbacks to work. To probably there must be some kind of Rollback flag.

[kreibaum]

Turns out this is super important, because it happens all the time when I have an AI running in the browser. Best to reproduce on a smartphone connected to the local dev environment.

[kreibaum]

This broke playing and I rolled it back with 0a920f0db6c000ec4ebce6fb357d25fb06d7f946

[kreibaum]

This time it actually worked and was an important ingredient in getting Hedwig to play online. The last commit actually closed this issue.