The French aren’t exactly famous for their warmth. Likewise, Paris Fashion Week isn’t known to feature designers whose collections can be worn off the rack, instead showcasing works of great sartorial ambition, with severe silhouettes and playful flourishes alike. Yet somehow, French writer-director Alice Winocour’s new film, “Couture,” which follows four women whose lives intersect during Paris Fashion Week, cuts through the austerity with all the precision and grace of a pair of fabric shears. Winocour’s filmmaking itself is as steely as a Parisian’s gaze after you order the last croissant à la pâtisserie. But something special happens when her simple yet stylish camera meets the gaze of her star, Angelina Jolie. The gray skies part, the clouds lift and a warm maternal comfort spreads across the film, creeping in like the sun’s rays falling on cobblestones still shining from a sudden downpour. Don’t be mistaken: “Couture” is not a happy film, at least not in the traditional sense. There is no tidy ending, or even a sense that everything will be alright. But Winocour …