There was a long seven-year hiatus between “A Visit From the Goon Squad” — the multifaceted, phantasmagorical best-selling novel that won Jennifer Egan a Pulitzer Prize and a host of new fans — and her newly released follow-up, “Manhattan Beach.” And she’s not any happier about it than anyone else. “I hope that never happens again,” Egan said firmly during a recent interview in the elegantly inviting Pacific Heights home of her mother and stepfather.