SnatcherBugFix

Fixes a couple of bugs related to snatchers/pouncers:

1. Fixes the pouncer screen effect failing to be applied when in a different menu page is open (map, lobby, etc), and failing to be removed when the player is spat out.
2. Prevents players from becoming trapped in the arena dimension.
3. (Host-only) Prevents survival waves and enemies from spawning in the arena dimension.
4. Fixes player locomotion and environment audio errors when spat out.
5. Makes the "black boxes" of the arena dimension appear invisible from other dimensions.

Thanks to Auri for the initial patch help, and Dinorush for their major contributions to this mod. Also big thanks to Tsopu, ThyUnsuspicious, and TheDoggyDoge for help testing.