The San Diego Symphony titled last Friday evening’s Jacobs Masterworks program “Tchaikovsky’s Third Symphony”, but when the audience rose to its feet in wonderfully noisy acclamation just before intermission, it was pretty clear that they had spontaneously re-named the evening “Jeff Thayer’s Second”, to honor the San Diego Symphony’s concertmaster for his impressive performance of one of the monuments of the violin repertoire, Béla Bartók’s Violin Concerto No. 2…