Sync messages shall be per client instead of being broadcasted

[CrazyFluffyPony]

This prevents weird behavior with multiple users using the companion at the same time (sync is detected and unlocks an element, even though it is the "wrong" sync).

This would require us to implement a way for the game to send data to some specific token.

[CrazyFluffyPony]

Problem: if a new vehicle is spawned by a player ingame, it would trigger a sync to all. So what to do now? Meeb