stream_info(ConnPid, StreamRef) -> {ok, undefined | Info} | {error, not_connected}

ConnPid :: pid()
StreamRef :: gun:stream_ref()
Info :: #{
    ref            => gun:stream_ref(),
    reply_to       => pid(),
    state          => running | stopping,
    intermediaries => [Intermediary],
    tunnel         => Tunnel
}
Intermediary :: #{
    type      => connect | socks5,
    host      => inet:hostname() | inet:ip_address(),
    port      => inet:port_number(),
    transport => tcp | tls,
    protocol  => http | http2 | socks | raw
}
Tunnel :: #{
    transport     => tcp | tls,
    protocol      => http | http2 | socks | raw,
    origin_scheme => binary() | undefined,
    origin_host   => inet:hostname() | inet:ip_address(),
    origin_port   => inet:port_number()
}

Info = gun:stream_info(ConnPid, StreamRef).