TOKYO—Simone Biles came to Tokyo as the star of the U.S. Olympic movement and perhaps the Games themselves. It all came to a stunning halt in the women’s gymnastics final on Tuesday night with an uncertain vault. In a flash, the rest of the American star’s Games came into question. And the United States’ long run at the top of the sport came to an end. The team representing the Russia Olympic Committee surged past the shorthanded United States to the top of the podium, posting a score of 169.258 to win the country’s first Olympic team gold in nearly 30 years. The Americans, with Biles serving as head cheerleader while clad in a white sweatsuit and dealing with what USA Gymnastics called a “medical issue,” hung on for silver. Grace McCallum, Sunisa Lee and Jordan Chiles drew the United States within eight-tenths of a point through three rotations. ROC, …