sway: split pipewire config into separate sane.programs.pipewire

hosts/common/programs/default.nix

@@ -69,6 +69,7 @@
     ./obsidian.nix
     ./offlineimap.nix
     ./open-in-mpv.nix
+    ./pipewire.nix
     ./planify.nix
     ./portfolio-filemanager.nix
     ./playerctl.nix

hosts/common/programs/pipewire.nix

@@ -0,0 +1,18 @@
+# administer with pw-cli, pw-mon, pw-top commands
+{ config, lib, ... }:
+let
+  cfg = config.sane.programs.pipewire;
+in
+{
+  services.pipewire = lib.mkIf cfg.enabled {
+    enable = true;
+    package = cfg.package;
+    alsa.enable = true;
+    alsa.support32Bit = true;  # ??
+    # emulate pulseaudio for legacy apps (e.g. sxmo-utils)
+    pulse.enable = true;
+    # TODO: try:
+    # socketActivation = false;
+  };
+  systemd.user.services."pipewire".wantedBy = lib.optionals cfg.enabled [ "graphical-session.target" ];
+}

hosts/common/programs/sway/default.nix

@@ -109,6 +109,7 @@ in
       "fuzzel"
       # "gnome.gnome-bluetooth"  # XXX(2023/05/14): broken
       # "gnome.gnome-control-center"  # XXX(2023/06/28): depends on webkitgtk4_1
+      "pipewire"
       "playerctl"  # for waybar & particularly to have playerctld running
       "pulsemixer"  # for volume controls
       "splatmoji"  # used by sway config
@@ -211,17 +212,6 @@ in
     });
   };
 
-  # unlike other DEs, sway configures no audio stack
-  # administer with pw-cli, pw-mon, pw-top commands
-  services.pipewire = lib.mkIf cfg.enabled {
-    enable = true;
-    alsa.enable = true;
-    alsa.support32Bit = true;  # ??
-    # emulate pulseaudio for legacy apps (e.g. sxmo-utils)
-    pulse.enable = true;
-  };
-  systemd.user.services."pipewire".wantedBy = lib.optionals cfg.enabled [ "graphical-session.target" ];
-
   # rtkit/RealtimeKit: allow applications which want realtime audio (e.g. Dino? Pulseaudio server?) to request it.
   # this might require more configuration (e.g. polkit-related) to work exactly as desired.
   # - readme outlines requirements: <https://github.com/heftig/rtkit>