Function handle_line 

async fn handle_line(
    dispatch: &ControlDispatchHandle,
    pending_controls: &Arc<Mutex<HashMap<String, Sender<Result<Value, Error>>>>>,
    inflight: &Arc<Mutex<HashMap<String, JoinHandle<()>>>>,
    events_tx: &UnboundedSender<Result<Message, Error>>,
    line_number: u64,
    line: &str,
    counters: &mut SkipCounters,
) -> LineOutcome

Process one decoded line. Returns LineOutcome::Stop only when the events channel has closed and the read loop should exit; a line that fails to decode is skipped and the loop continues.