HAVANA (AP) — The United States and Cuba will sign an agreement next week to resume commercial air traffic for the first time in five decades, starting the clock on dozens of new flights operating daily by next fall, U.S. officials said Friday. Barring other major announcements, it would be the most significant development in U.S.-Cuba trade since Presidents Barack Obama and Raul Castro announced in late 2014 that they would begin normalizing ties after a half-century of Cold War opposition. The Obama administration is eager to make rapid progress on building trade and diplomatic ties with Cuba before the president leaves office. Commercial flights could bring hundreds of thousands more U.S.