treewide: include PipeWire op and enforce PulseAudio check

This fully replaces PulseAudio with PipeWire and enforces the PulseAudio check and error message. The pipewire-pulse daemon is handled in the NixOS module.

Closes #26.

Signed-off-by: Ophestra <cat@gensokyo.uk>

cmd/hpkg/build.nix

@@ -176,7 +176,6 @@ let
       x11 = allow_x11;
       dbus = allow_dbus;
       pipewire = allow_audio;
-      pulse = allow_audio;
     };
 
     mesa = if gpu then mesaWrappers else null;