Comic-Con International’s first big day Friday, July 21, will be all about big TV franchises. AMC’s universe of “The Walking Dead” shows will take over Hall H for nearly three hours. Also attending will be Prime Video’s latest show in “The Boys” franchise, “Gen V”, and Peacock’s “The Continental,” a show based in the “John Wick” universe. There will also be the premiere of the DC animated film “Justice League: Warworld” and the cast of the second season of Prime Video’s “Good Omens” will have a panel with the cast. Here are some highlights with official descriptions courtesy of the…