Fix client rollbacks

[AudranTourneur]

The game sometimes "rollbacks" resulting in stuttering in which the player is teleported back to its previous position in an annoying manner.
When this happens, the following warn log is emitted in the console:

This happens when the client-side prediction system predicts an erroneous position which is then corrected by the server. This should in theory (almost) never happens in single-player, so there is clearly an implementation bug to discover.