By Andrew Goudsward WASHINGTON (Reuters) -A U.S. appeals court on Friday narrowed but largely upheld a gag order that bars Donald Trump from assailing prosecutors, court staff and potential witnesses in a federal criminal case that accuses him of illegally trying to overturn his 2020 election loss. A three-judge panel of the U.S. Court of Appeals for the District of Columbia Circuit kept most of the restrictions imposed by the original order, but lifted the prohibition on Trump personally criticizing Special Counsel Jack Smith, who is overseeing the prosecution. The court also narrowed the lim…