Navidrome: Add missing steps, unit, config

run/navidrome/workspace/syncthing.service

@@ -0,0 +1,28 @@
+[Unit]
+Description=Syncthing - Open Source Continuous File Synchronization for photoprism
+Documentation=man:syncthing(1)
+After=network.target
+StartLimitIntervalSec=60
+StartLimitBurst=4
+
+[Service]
+User=navidrome
+ExecStart=/usr/bin/syncthing serve --no-browser --no-restart --logflags=0 --home /var/lib/navidrome/syncthing --no-default-folder --gui-address=":8384"
+Restart=on-failure
+RestartSec=1
+SuccessExitStatus=3 4
+RestartForceExitStatus=3 4
+
+# Hardening
+ProtectSystem=full
+PrivateTmp=true
+SystemCallArchitectures=native
+MemoryDenyWriteExecute=true
+NoNewPrivileges=true
+
+# Elevated permissions to sync ownership (disabled by default),
+# see https://docs.syncthing.net/advanced/folder-sync-ownership
+#AmbientCapabilities=CAP_CHOWN CAP_FOWNER
+
+[Install]
+WantedBy=multi-user.target