CameraSkybox becomes a weighted layer list (ghost > WMO > zone, modern
crossfade), flags 0x1 day cycle / 0x2 keep celestial / 0x4 fog cone, the
celestial model as a second layer, and a CPU rig + mat-anim rows so skybox
bones, texture transforms, colour and alpha tracks play.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>