If the phrase cabaret act makes you think of soporific sentimentality, take in a Diana Krall show. The Canadian singer-pianist transforms venues like Chicago’s Jazz Showcase (Nov. 19-24) and the Oak Room at New York’s Algonquin Hotel from stuffy musical museums into gritty roadhouses. Live, as on her latest CD, All for You (a Nat King Cole homage that’s been on Billboard‘s jazz chart for 33 weeks), Krall, 30, infuses standards with an Elvis Costello-like attitude. ”You don’t go into jazz to be a rock star,” she says. ”You just hope to survive.” Krall’s got the best of both worlds.