Some albums unfold. Confident unfurls like a flag on a battlefield. Demi goes hard, holding notes with a passion yet unseen. She purges herself of tough lessons learned on “Old Ways,” “Lionheart” and “Waitin for You.” Even vulnerable moments, like “Stone Cold” and “For You,” are full of muscle and sinew, more apt to put a fist through a wall than to lick a wound. When she takes time to count the wins on pop-EDM bangers “Cool for the Summer” and “Stars,” her joy and relief wash over like a cleansing rain. Whatever struggle life throws at you, Confident has an anthem for that.