U.S.-backed members of Venezuela’s opposition converged on the Colombian border city of Cúcuta to arrange a new challenge against Venezuela’s autocratic leader, Nicolás Maduro: food shipments that would be transported into the crisis-stricken country in coming days. Venezuelan exiles working with Juan Guaidó, the opposition leader the U.S. and other countries recognize as the nation’s interim president, on Tuesday had started shipping nutritional biscuits for malnourished children by truck to Cúcuta from Colombia’s capital…