It’s the same old song when it comes to Kawhi Leonard and his availability for the Clippers when they meet the Dallas Mavericks in Game 1 of the Western Conference playoffs on Sunday at Crypto.com Arena. It remains uncertain — a mystery even — if Leonard will play in the first game of the best-of-seven series. He missed the last eight games of the regular season because of right knee inflammation. The Clippers had their first practice Tuesday in preparation for the Mavericks, leaving the media to ask coach Tyronn Lue if Leonard would fully practice. “No, not fully,” Lue said. “But he’s going to be a part of practice.” Lue was asked how much Leonard can participate in practice. “Um, he’s going to do a quarter of the practice,” Lue said. LIke running, Lue was asked. “Just a quarter of the practice, yeah,” Lue responded. Is it because Leonard hasn’t played in an NBA game since March 31? “Yeah, just bring him along slowly,” Lue said. By the time Sunday rolls arrvies, Leonard will have missed three weeks of NBA game action. So, Lue