TOKYO—It will be an Olympics like no other, the world’s largest mega-sports event being staged in the middle of a pandemic. Tokyo organizers and the IOC on Wednesday began explaining in public just how they hope to do it, rolling out “Playbooks” to detail the ways that 15,400 athletes will enter Japan—and exit Japan—with the Olympics opening on July 23 and the Paralympics a month later. “There are indeed a lot of questions in the public domain about how the games will take place this summer. And today is a preliminary review of how things will be done,” Olympic Games executive director Christophe Dubi said in a video news conference with Tokyo officials. The rollout of the Playbooks is aimed at assuring athletes, and an attempt to convince the Japanese public that the Olympics should go ahead. Polls across Japan show up to 80 percent want the Olympics postponed or canceled. The …