NEW YORK — Lights, camera, pause. Hollywood is officially on hiatus as the union representing on-screen talent has joined screenwriters in striking against the studios, amid stalled contract negotiations. SAG-AFTRA officially announced its strike would commence at midnight PST Friday, after the union’s contract expired late Wednesday and negotiations with the Alliance of Motion Picture and Television Producers (AMPTP) fell apart. Union leadership noted that while the strike was “an instrument of last resort,” settling for an unfair deal wouldn’t just “destroy each of us, but the industry at la...