MICHELE KAMBAS and GEORGE GEORGIOPOLOUS COMPOSER Mikis Theodorakis, whose life and music mirrored Greece's soul and crossed international boundaries in his captivating score for the film "Zorba the Greek", died on Thursday, plunging the country into three days of mourning. A towering man with a brooding presence and a shock of wavy hair, Theodorakis's work evoked a progressive, democratic vision of the world, though his political struggles reflected a darker side of Greece rarely seen by visitors. As news of his death at home in Athens at the age of 96 swept across the country of 11 million, authorities declared…