Connection string or SyncServerSpec.
Valid connection strings:
usbnet or networkserial:/dev/ttyXXX (serial:COMn on Windows)serial:/dev/ttyXXX:19200 to specify max baud rateserial:net or serial:network for serial-over-network (POSE and
other emulators)serial:web or serial:web-serial for Web SerialSync function to run for new connections.
Additional options for the sync connection.
Create a sync server from a connection string or SyncServerSpec.