Merge branch 'master' into next

Carries the Nym mixnet transport + single-container demo.

Forward-merge adaptation: the Nym end-to-end SOCKS5 send/recv test was
authored against master's IK FMP framing (msg1 wire size 114, version
nibble 0). next uses the XX handshake and FMP v1, so the TCP read path
rejected the test frame (UnknownVersion / HandshakeSizeMismatch),
timing the test out. Adapted build_msg1_frame to next's framing (wire
size 41, ver=1/phase=1 header byte). next-only; master keeps its IK
form.

src/node/mod.rs

@@ -64,6 +64,7 @@ use crate::peer::{ActivePeer, PeerConnection};
 use crate::protocol::NodeProfile;
 #[cfg(unix)]
 use crate::transport::ethernet::EthernetTransport;
+use crate::transport::nym::NymTransport;
 use crate::transport::tcp::TcpTransport;
 use crate::transport::tor::TorTransport;
 use crate::transport::udp::UdpTransport;
@@ -1007,6 +1008,21 @@ impl Node {
             transports.push(TransportHandle::Tor(tor));
         }
 
+        // Create Nym transport instances
+        let nym_instances: Vec<_> = self
+            .config()
+            .transports
+            .nym
+            .iter()
+            .map(|(name, config)| (name.map(|s| s.to_string()), config.clone()))
+            .collect();
+
+        for (name, nym_config) in nym_instances {
+            let transport_id = self.allocate_transport_id();
+            let nym = NymTransport::new(transport_id, name, nym_config, packet_tx.clone());
+            transports.push(TransportHandle::Nym(nym));
+        }
+
         // Create BLE transport instances
         #[cfg(bluer_available)]
         {