Bob Dylan became the first musician tabbed for the American Academy of Arts and Letters this spring but skipped the April dinner and last night's induction. He did promise that "I look forward to meeting all of you some time soon." So the highlight was novelist Michael Chabon claiming that long ago he was certain the opening line of "Chimes of Freedom" referred to a "broken toe," not a "broken toll." Chabon: "Far between sundown's finish and midnight's broken toe. How many hours I had devoted to (the idea) . . . that midnight had toes, and that one of them, the big one, had been broken." The Byrds' version, introduced by Bert Lahr no less.