Meghan Markle and Prince Harry, like the rest of the U.S., are looking forward to a low-key Thanksgiving dinner this year.A source close to the couple tells ET, "[Meghan and Harry] are going to have a quiet dinner at home and are looking forward to celebrating their first American Thanksgiving in the States as a family. They plan to enjoy a home-cooked meal with traditional Thanksgiving dishes, including recipes made with fresh vegetables from their garden.«The couple, and son Archie, will be