Refactor Nix configurations for improved readability and organization; update package declarations to use 'with pkgs;' syntax and remove unnecessary builtins.attrValues.

hosts/common/optional/audio.nix

@@ -1,7 +1,6 @@
 # NOTE(starter): configure your audio needs as required.
-{ pkgs, ... }:
-{
-  hardware.pulseaudio.enable = false;
+{pkgs, ...}: {
+  services.pulseaudio.enable = false;
   security.rtkit.enable = true;
   services.pipewire = {
     enable = true;
@@ -12,10 +11,8 @@
     jack.enable = true;
   };
 
-  environment.systemPackages = builtins.attrValues {
-    inherit (pkgs)
-      playerctl # cli utility and lib for controlling media players
-      # pamixer # cli pulseaudio sound mixer
-      ;
-  };
+  environment.systemPackages = with pkgs; [
+    playerctl # cli utility and lib for controlling media players
+    # pamixer # cli pulseaudio sound mixer
+  ];
 }