reaction implementation

[dkuss-tudresden]

Can you please add a similar reaction handling as in "motion_waypoint_generator.hpp" to all other motion generators?

A full implementation with reaction movements would be optimal,
transitionally a stop command would also do:

        for (auto& reaction : data.reactions) {
            if (reaction.has_fired) {
                continue;
            }

            if (reaction.condition(MotionGenerator::convertState(robot_state), time)) {
                std::cout << "[frankx] reaction fired." << std::endl;
                reaction.has_fired = true;

                bool new_motion = false;
                robot->stop();
                return franka::MotionFinished(CartesianPose(trajectory.path.q(s_current, frame), use_elbow));
                //return franka::MotionFinished(MotionGenerator::CartesianPose(input_para.current_position, waypoint_has_elbow));
            }
        }