docs(cable): note PXP-over-BLE data channel support

Adds a README feature line for the direct BLE L2CAP data channel, and
updates the cable example wording since the channel is no longer always
a tunnel. The example exercises PXP-over-BLE unchanged: the QR code
advertises BLE and connection_stage selects L2CAP when offered.

Author: AlfioEmanueleFresta

README.md

@@ -37,6 +37,7 @@ _Looking for the D-Bus API proposal?_ Check out [credentialsd][credentialsd].
   - 🟢 Discoverable credentials (resident keys)
   - 🟢 Hybrid transport (caBLE v2): QR-initiated transactions
   - 🟢 Hybrid transport (caBLE v2): State-assisted transactions (remember this phone)
+  - 🟢 Hybrid transport (PXP / CTAP 2.3): direct BLE L2CAP data channel, QR-initiated, no tunnel server
 
 ## Runtime requirements
 

libwebauthn/examples/ceremony/webauthn_cable.rs

@@ -86,7 +86,7 @@ pub async fn main() -> Result<(), Box<dyn Error>> {
         println!("{}", image);
 
         let mut channel = device.channel().await.unwrap();
-        println!("Tunnel established {:?}", channel);
+        println!("Channel established {:?}", channel);
 
         let state_recv = channel.get_ux_update_receiver();
         tokio::spawn(common::handle_cable_updates(state_recv));
@@ -118,7 +118,7 @@ pub async fn main() -> Result<(), Box<dyn Error>> {
     .unwrap();
 
     let mut channel = known_device.channel().await.unwrap();
-    println!("Tunnel established {:?}", channel);
+    println!("Channel established {:?}", channel);
 
     let state_recv = channel.get_ux_update_receiver();
     tokio::spawn(common::handle_cable_updates(state_recv));