Leading stock market indexes opened in record territory, with investors buoyed by signs of progress on a U.S.-China trade deal.Shortly after the start of trade on Friday, the S&P 500 rose 14 points, or 0.2%, to 6,155 points, surpassing its previous all-time closing high in February of 6,144. The index also briefly edged above its previous record on Thursday in intraday trading.The Nasdaq Composite gained 62 points, or 0.3 %, to 20,227, topping its previous record high of 20,174 on Dec. 16, 2024. The Dow Jones Industrial Average rose 0.4%...