Photos by Mark C. AustinAftermath had literally no idea what to expect at Sunday afternoon's Jandek show at Rudyard's, the first-ever public performance in Houston by one of the world's leading "outsider" musicians (who just happens to live here). From the little he knows of Jandek's prodigious catalogue, his best guess would have been a somewhat downcast solo performance on scratchy acoustic guitar. A one-song, 75-minute atomic funk explosion by way of the Knitting Factory was about the