01 /How Reality hides a connection
Your app opens a TCP connection to the node on port 443 and starts an ordinary TLS 1.3 handshake. The server name in it is a large website that has nothing to do with the node: the operator picks one, or the node software picks one the node can reach. The app shapes the handshake like Chrome's, so on the wire it looks like a browser visiting that site.
Only a client that holds the node's public key and short ID gets a VPN session. Anything else, including a censor's active probe, is passed through to the real website and receives that website's genuine certificate. There is no home-made certificate to spot and no VPN greeting to find.