//! Network utility helpers.
/// Detect a local non-loopback IPv4 address for LAN display.
pubfnlocal_ip()->Option<String>{let socket =std::net::UdpSocket::bind("0.0.0.0:0").ok()?;
socket.connect("8.8.8.8:80").ok()?;Some(socket.local_addr().ok()?.ip().to_string())}