Colombian salsa legend Fruko is appearing as a special guest of Classico Latino in a concert in Cambridge later this month. The 72-year-old multi-instrumentalist is Colombia’s most famous salsa star, and has made more than 40 albums with his band Fruko y sus Tesos since 1969. But after a chance meeting with a friend of Cambridge cellist Graham Walker, one of the founders of the group Classico Latino, which plays Latin music on classical instruments, he agreed to a new collaboration. Now the group has brought out an album covering seven of Fruko’s most famous tracks in brand new arrangements fo…