chore: move mpd, also add some things and reorder

modules/services/mpd.nix

@@ -1,31 +0,0 @@
-{
-  username,
-  config,
-  pkgs,
-  ...
-}:
-{
-  services.mpd = {
-    enable = true;
-    musicDirectory = "/home/liv/Music";
-    extraConfig = ''
-      audio_output {
-        type "pipewire"
-      	name "pipewire"
-      }
-    '';
-    user = "${username}"; # PipeWire requires this as it runs as the normal user and mpd normally runs as a system user.
-
-    # Optional:
-    # network.listenAddress = "any"; # if you want to allow non-localhost connections
-  };
-  systemd.services.mpd.environment = {
-    # see: https://gitlab.freedesktop.org/pipewire/pipewire/-/issues/609
-    XDG_RUNTIME_DIR = "/run/user/${toString config.users.users.${username}.uid}"; # User-id must match above user. MPD will look inside this directory for the PipeWire socket.
-  };
-
-  environment.systemPackages = with pkgs; [
-    mpdris2
-    ncmpcpp
-  ];
-}