Disney returned to its spot as the undisputed leader of the box office in 2024, but the poor opening weekend of “Mufasa: The Lion King” threatens to end the year on a sour note. Were it any other time of the year, the $35 million domestic/$122 million global opening of this Barry Jenkins-directed prequel to the 2019 “Lion King” remake — well short of pre-release projections of $50 million and $180 million — would be a sign of an impending flop. But this is Christmas, a time of miracles… and