feat(node): push USB changes and preserve sensor setup across sessions

apps/node-agent/cmd/node-agent/main.go

@@ -115,6 +115,7 @@ func run() error {
 	go func() { errs <- private.Serve(unix) }()
 	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
 	defer stop()
+	go app.Sensors.WatchUSB(ctx)
 	go pairing.Run(ctx)
 	log.Print("Mission Core Node " + version + " listening on loopback")
 	select {