Less than a week after rushing to Ground Zero as a police chaplain on 9/11, Rabbi Alvin Kass led Rosh Hashanah services, not only for his Brooklyn congregation but at a makeshift synagogue at LaGuardia Airport for emergency responders who had flooded into New York City after the terrorist attacks.“It was,” he would later say, “the most meaningful religious service in my career.”Kass died early Wednesday at 89 as the longest-serving chaplain in the New York Police Department, with a career that