The two main contenders in Ghana’s presidential election have launched duelling manifestos promising fiscal stability, jobs and a path out of the country’s worst economic downturn in a generation.Voters will head to the polls on December 7 to elect a successor to President Nana Akufo-Addo, who is stepping down at the end of the two terms he is allowed to serve as head of the West African gold, oil and cocoa-producing nation.The election will pit ex-president John Dramani Mahama of the main opposition National Democratic Congress party against Vice President Mahamudu Bawumia, an…