INSIDE THE COSTUME SHOP at Pacific Northwest Ballet, worktables are covered with sketches and pieces of fabric — and not a single computer. Rob Newton uses a pencil to trace a leaf pattern made from tagboard. It’s less than three weeks out from the late March opening of “Momotaro,” a new ballet commissioned for PNB, and Newton has a dozen dancing peach costumes to make. A single leaf consists of 16 parts, all cut by hand. “AI will never take our jobs,” he says. “We’re couture.” On average, a single costume takes 100 hours to make and “some are waaaay more than that,” says Meleta Buckstaff, PNB’s costume shop manager. The ornate king’s coat in “The Sleeping Beauty,” for example, took seven months to make. These are not costumes you can order off Temu. All this, for a costume that might whirl across the stage for mere minutes. Inside PNB’s home at Seattle Center, the windows of the costume shop overlook dancers rehearsing downstairs.…