The much-anticipated “Game of Thrones” prequel, “House of the Dragon,” introduces us to a whole new cast of characters. Set centuries before “Game of Thrones,” the series follows the conflicts and drama of House Targaryen, the powerful, dragon-riding royal family who rule Westeros. Among the many new characters we’ll be meeting is Aegon Targaryen, who may appear to be just one of many family members but, in fact, is set to become one of the saga’s pivotal characters. Sharing a name with…