What does it mean that there is a plaque "You Yong in the Imperial Vault" in chengde mountain resort Shenting?

Jinshan Shenting was built in imitation of Jinshan Temple in Zhenjiang, Jiangsu Province. Gu Lou has a pavilion on the first floor, a building on the second floor and a pavilion on the third floor. Jinshan Shenge is a three-story building, the first floor is dedicated to the royal family of the Qing Dynasty, the second floor is dedicated to the northern god Xuanwu the Great, and the third floor is dedicated to the Jade Emperor. Jinshan Shenting is the highest point in the lake area, and it used to be a place to worship heaven. The Empire State Building in You Yong is blessed by heaven.