District Pour & Provisions is poised to become the first of three new food halls to open in Westminster. Molly Mart You might think of them as Schrödinger’s snack spots: In the Denver metro area, the food hall trend seems to be either fading fast or flourishing — at the same time. Denver’s first “food hall,” the Yum Yum Tree, actually showed up way back in 1968. The operation on South Colorado Boulevard was far from fancy, and it was just called a food court. In the modern food hall era, The Source came on the scene in 2013. It…