Map doesn't sync when changing dimensions in the same way it does when joining the game

[sisby-folk]

Explore two dimensions and nuke your client player-exploration, then rejoin the server.

Terrain becomes fully explored in the join dimension, but not a dimension you travel to after.

Tested on the mf1.21 configuration (terrain NONE global sharing TRUE)

[sisby-folk]

might need some kind of "client cheater" switch for these types of situations, where we don't want terrain sync but do want to show all the data packed into the pack