NEW YORK — A swath of Americans watching President Joe Biden is seeing something beyond debate-stage stumbles and prime-time miscues: Themselves. “But you’ve got to keep working, no matter what.” D’yan Forest, 89, who holds the Guinness World Record for Oldest Working Female Comedian, poses in her apartment, Thursday, July 19, 2024, in New York. “What’s happening now,” the 91-year-old …