The Sixers still have to clear enough space under the luxury-tax apron to gain access to the non-taxpayer mid-level exception. Philadelphia 76ers guard James Harden officially declined his $47.4 million player option for the 2022-23 season on Wednesday, a source confirmed to Liberty Ballers. Shams Charania of The Athletic was the first to report the news. Harden is now set to become an unrestricted free agent at 6 p.m. ET on Thursday, June 30, although his return to the Sixers appears all but preordained. “As you guys have heard, it’s a mutual lovefest, so we feel like we’ll work it…