A pair of prototype Nikes worn by Kanye West during his performances of “Hey Mama” and “Stronger” at the Grammy Awards in 2008 has shattered the record for a pair of sneakers ever sold. Sotheby’s announced Monday that West’s so-called “Grammy Worn” Nike Air Yeezy 1 fetched $1.8 in a private sale. “We are thrilled with the result, which has …