It would be easy for a journalist to be jealous of a novelist. Journalists must adhere to the facts, while novelists can manipulate the facts to suit the narrative. (Don’t start with your opinions about the news media. That’s a conversation for another time.) But while journalists can report the facts and consider it truth, novelists must adhere to an abstract concept of artistic truth that is much, much harder to execute. So to speak. Which explains “Infamous” (2006), the story of “In Cold Blood” and the mentally tortuous route through the gallows that Truman Capote took in creating it.