The UN humanitarian aid and refugee agencies appealed Wednesday for $4.1 billion in international support for embattled civilians in Sudan amid signs that some may be dying of starvation after nearly a year of war there between the forces of rival generals. In their joint appeal, the refugee agency, UNHCR, and the UN Office for the Coordination of Humanitarian Affairs said that half of Sudan’s population, or some 25 million people, requires support and protection. They said the requested funds would go to help millions of civilians in Sudan and others who have fled abroad. “They have lost so m…