pub fn start_oauth_callback_server(
redirect_uri: &str,
) -> Result<OAuthCallbackServer>Expand description
Start a local TCP listener on the port specified in redirect_uri.
The server accepts exactly one connection, responds with a friendly HTML page
so the browser shows “You can close this tab”, and sends the full callback URL
through the returned OAuthCallbackServer.rx.
Returns Err if the redirect URI does not contain a parseable port or the
port cannot be bound.