Warp song cutscenes were skipped for randomizer players whether they
wanted it or not: Demo_Kankyo cut the departure animation short from a
hardcoded IS_RANDO branch, and entrance rando cleared respawnFlag so the
arrival never played. There was no way to get the vanilla warp back, and
no way for a vanilla playthrough to skip it.

Drop both and put the behavior behind a Skip Warp Cutscenes toggle,
defaulting on in randomizer so existing rando warps are unchanged. It
kills the departure actor as it spawns and puts the arrival spawn mode
back to IDLE, which covers both halves of the warp.

Entrance rando's destination override moves off Demo_Kankyo's update onto
a new OnWarpSongLeave hook fired from Environment_WarpSongLeave. That is
where every warp path -- the cutscene, the skip toggle, and the spawn
failure fallback -- commits its destination, so the override no longer
depends on the departure actor being alive to see it, and a warp song
shuffled onto a grotto return keeps its grotto respawn.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Rename various variables across codebase to match decomp,
many had been renamed when exposed for previous save state mechanism