As meditation on the doomed love affair between the poet John Keats (Ben Whishaw) and Fanny Brawne (Abbie Cornish), Jane Campion’s Bright Star is not a typical period film. Critics have praised this intimate, unadorned romance since it premiered at Cannes this spring, as set decorator Charlotte Watts tells us, recreating its sets—all the way down to the upholstery nails—was …