A house in Aspen just set a new record. The property at 135 E. Cooper Ave. sold for $21.95 million late last month, but that’s not where the record-setting money resides in this residence nestled in the core of Aspen. “This is the highest price-per-square-foot sale for a single-family home in the central downtown area of Aspen,” said Carrie Wells, a broker with Coldwell Banker Mason Morse Real Estate, who represented the seller of the J.M.