- UtunNode runs uTun instance in a dedicated std::thread
- no TUN, no msg_transport — direct etcp_route_send/recv calls
- Thread-safe cross-thread communication via Qt signals
- C callback (etcp_recv_fn) stores UtunNode* via thread_local
- etcp_router_bind on service ID 0x11 for chat messages
- uasync_poll(100ms) loop runs until stop() called
Evgeny