Exposes SSHClient + SSHTerminalListener to the Android app. Connect()
auto-detects the server type via banner inspection and selects the auth
path: NetBird-SSH with JWT triggers the device-code OAuth flow via the
existing URLOpener; NetBird-SSH without JWT uses the NetBird private
key; regular SSH falls back to NetBird key then optional password. The
client dials through the running tunnel using a plain net.Dialer and
relies on the gomobile-bound listener for streaming PTY output back to
Java for rendering in an xterm.js WebView.
a94dfd732f