Senator Chuck Schumer, the majority leader, is planning to lead a bipartisan delegation of senators to China this fall, making him the highest-level congressional official and the latest senior statesman to visit the United States’ rival superpower as the Biden administration attempts to address tensions with Beijing through an all-out diplomatic push. The delegation, which Mr. Schumer will lead alongside Senator Michael D. Crapo, Republican of Idaho, also plans to make stops in Japan and South Korea, according to spokespeople for both senators’ offices. The planned visit was reported earlier…