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>

hst/hst_test.go

@@ -105,8 +105,7 @@ func TestTemplate(t *testing.T) {
 	"enablements": {
 		"wayland": true,
 		"dbus": true,
-		"pipewire": true,
-		"pulse": true
+		"pipewire": true
 	},
 	"session_bus": {
 		"see": null,