“The Lifespan of a Fact” is a poppy procedural and socially conscious comedy about facts, falsehoods, the nature of non-fiction, the boundaries of creative license, and the ethics of journalism.  Bobby Canavale, Cherry Jones, and Daniel Radcliffe are a radiant trio in Leigh Silverman’s swift and entertaining production.  This is the Trump-era play we’ve been waiting for: smart and funny, with a serious message about the importance of facts and fact-checking to the trust and integrity of institutions.