Marvel’s star-studded Avengers superhero team descended on Los Angeles on Monday at a lavish premiere to celebrate the final chapter in a 22-movie saga that ranks as the movie industry’s highest-grossing franchise of all time. Hundreds of industry VIPs, cast members, fans and media watched the first showing of “Avengers: Endgame,” the three-hour action spectacle that has been held tightly under wraps. The movie begins rolling out in theaters around the world on Wednesday. Robert Downey Jr. (Iron Man), Chris Hemsworth (Thor), Scarlett Johansson (Black Widow), Chris Evans (Captain America), Brie Larson (Captain Marvel) and others walked a purple carpet underneath a giant, spinning Avengers logo set up inside the Los Angeles Convention Center. “I’m excited that I’m finally going to get to see the movie,” said Paul Rudd, who plays Ant-Man and, like other cast members, had not seen the finished film due to Marvel’...