Function format_is_packet_with_qconstruct 

pub fn format_is_packet_with_qconstruct(
    source: &str,
    destination: &str,
    path: &[&str],
    qconstruct: QConstruct,
    gate_callsign: &str,
    data: &str,
) -> String

Format an APRS-IS packet with an explicit Q-construct.

Injects the Q-construct just before the gate callsign — the form required for packets originated by a client application. Per the APRS-IS spec, clients add qAC or qAX depending on whether they authenticated.