feat(x11): disable X screensaver/DPMS blanking and enforce explicit-only locking

overlay/rootfs/usr/bin/sxmo_dwminit.sh

@@ -20,7 +20,7 @@ envvars() {
 
 defaults() {
 	xsetroot -solid '#1c1c1c'
-	xset s off -dpms
+	xset s off s noblank s 0 0 -dpms
 	[ -e "$HOME"/.Xresources ] && xrdb -merge "$HOME"/.Xresources
 	if [ -f /usr/share/wallpapers/bananarchy.png ] && command -v feh >/dev/null 2>&1; then
 		feh --no-fehbg --bg-fill /usr/share/wallpapers/bananarchy.png &