BUENOS AIRES, Argentina — A long-lost Italian portrait looted from a prominent Jewish art dealer during the Second World War was set to be returned to his heir after an Argentine court on Friday approved a deal under which the daughter of a fugitive Nazi official agreed to give up her claim rather than face trial.The agreement paves the way for the long-sought return of “Portrait of a Lady” to Marei von Saher, the sole surviving heir of Dutch-Jewish art dealer Jacques Goudstikker, whose celebrated collection was sold under duress to Nazi officials after Adolf Hitler’s Germany invaded the Netherlands...