music: Set up ampswitch for MPD and Librespot

roles/music/templates/ampswitch.service

@@ -0,0 +1,20 @@
+[Unit]
+Description=Script hook for {{ item }} playback
+After=network.target {{ item.instance }}.service
+Requires={{ item.instance }}.service
+StopPropagatedFrom={{ item.instance }}.service
+
+[Service]
+Type=simple
+Restart=always
+RestartSec=10s
+ExecStart=/usr/bin/pw-jack ampswitch --jack-name ampswitch-{{ item.instance }} --on-command /opt/on-{{ item.instance }}-start.sh --switch-time 10 --trigger-level 0.001
+ExecStartPost=/usr/bin/sleep 4
+{% for pw_input in item.pw_inputs %}
+ExecStartPost=-/usr/bin/pw-link "{{ pw_input }}" ampswitch-{{ item.instance }}:Input
+{% endfor %}
+User=root
+Environment="XDG_RUNTIME_DIR=/run/user/{{ music_audio_user_id }}"
+
+[Install]
+WantedBy=multi-user.target