pinephone-pro: plumb backlight through to swaync (though apparently i still disable this, in favor of nwg-panel)

hosts/modules/hal/pine64-pinephone-pro/default.nix

@@ -36,6 +36,11 @@ in
       "pine64-alsa-ucm"  # upstreaming: https://github.com/alsa-project/alsa-ucm-conf/pull/375
     ];
 
+    # sane.programs.nwg-panel.config.torch = "white:flash";  #< TODO: enable the flashlight/torch
+    sane.programs.swaynotificationcenter.config = {
+      backlight = "backlight";  # /sys/class/backlight/*backlight*/brightness
+    };
+
     boot.kernelPatches = [
       {
         # TODO: upstream into nixpkgs. <repo:nixos/nixpkgs:pkgs/os-specific/linux/kernel/common-config.nix>