The heads of the world’s largest technology companies are all competing to sustain their dominance in a world reshaped by artificial intelligence. Amazon.com Inc. said it is going to reduce its work force as AI handles more tasks, Meta just invested more than $14 billion in Scale AI and Apple has weighed bidding for Perplexity AI.Down here in Los Angeles, most studios, producers and talent agencies are preoccupied with other topics — the summer movie slate, the flight of production and the uncer...