Add systemd unit to debian package

.github/workflows/go.yml

@@ -34,7 +34,7 @@ jobs:
         if: matrix.os == 'linux'
         uses: bpicode/github-action-fpm@master
         with:
-          fpm_opts: -s dir -t deb -n mdns2mqtt -a ${{ matrix.arch }} -v ${{ steps.version.outputs.version }} mdns2mqtt=/usr/bin/mdns2mqtt
+          fpm_opts: -s dir -t deb -n mdns2mqtt -a ${{ matrix.arch }} -v ${{ steps.version.outputs.version }} --deb-default debian/mdns2mqtt --deb-systemd debian/mdns2mqtt.service mdns2mqtt=/usr/bin/mdns2mqtt
       - name: Upload .deb package
         uses: actions/upload-artifact@v4
         if: matrix.os == 'linux'

debian/mdns2mqtt

@@ -0,0 +1,14 @@
+# The address of the MQTT broker to connect to
+MQTT_ADDRESS=
+
+# The credential to use when connecting to the MQTT broker
+# MQTT_USERNAME=
+# MQTT_PASSWORD=
+
+# The MQTT topic to publish locally discovered MDNS services to. Local discovery is disabled if unset.
+# MQTT_PUBLISH_TOPIC=
+# The MQTT topic to subscribe to. MDNS services received on this topic will be locally announced.
+# MQTT_SUBSCRIBE_TOPIC=
+
+# The interface to listed on and publish MDNS announcements to
+MDNS_INTERFACE=eth0

debian/mdns2mqtt.service

@@ -0,0 +1,9 @@
+[Service]
+Type=simple
+ExecStart=/usr/bin/mdns2mqtt
+RestartSec=5s
+Restart=always
+EnvironmentFile=-/etc/default/mdns2mqtt
+
+[Install]
+WantedBy=multi-user.target