Johanna Fernández holds some of the police surveillance records that she used in her research on her lap, in her home in New York, Aug. 8, 2014. Fernández, a Dominican American historian whose authoritative book about the Young Lords helped revive the legacy of that leftist collective, a revolutionary Latino counterpart to the Black Panthers, died on July 30, 2026, in Manhattan. She was 55. (Christopher Gregory-Rivera/The New York Times) By RICHARD SANDOMIR Johanna Fernández, a Dominican…