Function emit_param_change 

pub fn emit_param_change(
    changes: &mut EventQueue<ParamChanged, PARAM_CHANGED_QUEUE_CAPACITY>,
    id: ParamId,
    old: ParamValue,
    new: ParamValue,
)

Queue an onboard parameter-value update after a subsystem has changed a parameter directly. Sensor calibration uses this once its sample window completes, so the companion receives the resulting value as MAVLink PARAM_VALUE rather than only the command acknowledgement.