CursorRenderer now toggles Input.MOUSE_MODE_VISIBLE when gameplay is
occluded, restores MOUSE_MODE_HIDDEN when gameplay resumes. Without
this, fullscreen apps (star map, future atlas) had no cursor at all —
the custom diegetic cursor hid correctly but the system cursor was
never restored.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>