Function invoke_gate 

pub fn invoke_gate(
    _node: &NodeProto,
    inputs: &[(&str, &dyn SlotValue)],
    _ctx: &mut RuntimeResourceRef<'_>,
) -> Result<DispatchResult, OpError>

Gate(value, trigger) → value. Releases the value once trigger arrives (both inputs are required by all_inputs_ready before the engine invokes us).