Fix: Only create Sunshine headless output on desktop (no battery)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

dotfiles/.config/hypr/core/startup.lua

@@ -14,8 +14,8 @@ hl.on("hyprland.start", function()
     hl.exec_cmd("dbus-update-activation-environment --systemd WAYLAND_DISPLAY XDG_CURRENT_DESKTOP")
     hl.exec_cmd("systemctl --user import-environment WAYLAND_DISPLAY XDG_CURRENT_DESKTOP")
 
-    -- Sunshine
-    hl.exec_cmd("sleep 1 && hyprctl output create headless")
+    -- Sunshine (virtual monitor only on desktop; skipped on laptops, detected by a system battery)
+    hl.exec_cmd("sleep 1 && ! ls -d /sys/class/power_supply/BAT* >/dev/null 2>&1 && hyprctl output create headless")
 
     -- Polkit (Polkit Gnome / KDE)
     hl.exec_cmd(scriptsDir .. "/Polkit.sh")