SEOUL — Though the current South Korean president, Yoon Suk-yeol, has vowed to mend ties with Japan, the two countries have had a history of icy relations, especially under Mr. Abe. Mr. Yoon sent a telegram to Mr. Abe’s wife on Friday, expressing his “condolences and sympathy to the bereaved family and the people of Japan over the loss of its longest-serving former prime minister and a respected p