85513d1697
A host (re)started after a desktop login inherits the user manager's
compositor env; a stale WAYLAND_DISPLAY makes headless gamescope 3.16
exit at startup ('Failed to connect to wayland socket') before its
PipeWire node appears. Unset both on the systemd-run transient unit
(UnsetEnvironment=) and the direct spawn (env_remove) — gamescope
exports its own DISPLAY/GAMESCOPE_WAYLAND_DISPLAY to the nested app.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>