Complete iroh discovery when Iroh supports it

[andrewdavidmackenzie]

See code in find_piglets():

map.insert(
            trunc, // TODO substitute for real serial_number when Iroh discovery supports it
            DiscoveredDevice {
                discovery_method: IrohLocalSwarm,
                hardware_details: hw::driver::get().description().unwrap().details, // TODO show the real hardware description when Iroh discovery supports it
                ssid_spec: None,
                hardware_connection: HardwareConnection::Iroh(
                    remote.node_id,
                    remote.relay_url.map(|ri| ri.relay_url),
                ),
            },
        );

And get the additional properties via Iroh.

[andrewdavidmackenzie]

Submitted to Irho here: n0-computer/iroh#3037