By Jack Kim SEOUL (Reuters) -South Korea’s opposition Democratic Party leader Lee Jae-myung remained hospitalised in intensive care on Wednesday, a day after a knife attack on him shocked political leaders who were vying for the upper hand in a major election three months away. Surgeons operated on Lee for more than two hours late on Wednesday to repair a major blood vessel in his neck that was sliced when an assailant lunged and stabbed him with a knife. “The act of terror against Chairman Lee Jae-myung was clearly a challenge against democracy and a threat against democracy,” Democratic Part…