Of all the multifold moods and personalities that course through the music of Leonard Bernstein, there are two traits that stand out as particularly characteristic — his jazzy energy and his tender, sometimes sodden sentimentality. And those were the focus of Friday night’s exuberant and ingratiating all-Bernstein concert by Michael Tilson Thomas and the San Francisco Symphony in Davies Symphony Hall. The program marked the beginning, aside from the glittery “Candide” Overture that launched the orchestra’s season-opening gala concert last week, of a yearlong observation to the composer’s centennial — which is in 2018, but I suppose there’s no harm in celebrating early.