A 10-foot-tall sculpture made of 2,000 cast-aluminum high-heeled shoes is packing up and leaving its longtime perch outside Caleres headquarters in Clayton, bound for a new life greeting travelers at St. Louis Lambert International Airport. The footwear company is donating the piece, known as “Shoe of Shoes,” to the airport, which plans to spend $15,000 to move, clean and power-wash the sculpture before installing it on a grassy area west of the…