LAS VEGAS — A last-minute settlement avoided trial Tuesday in a massive civil breach-of-contract lawsuit involving casino giant MGM Resorts International and six of seven contractors on a never-opened Las Vegas Strip tower called the Harmon. Several jurors gasped when Clark County District Judge Elizabeth Gonzalez announced the parties reached an agreement that avoided a trial that lawyers for MGM Resorts and general contractor Tutor Perini Corp. had said could take a year or more. The eight men and 12 women …