“Matters of great concern should be treated lightly,” intones the eponymous hero of Jim Jarmusch’s sublime Ghost Dog: The Way of the Samurai , about a New York City hit man who has styled himself as a sort of time-warped expatriate of feudal Japan. He lives humbly among his pigeons and under the dual sign of the I Ching and the Wu-Tang, wielding katana and karma alike as precision instruments. Study Jim Jarmusch’s blade and you’ll find that he also likes to cut things fine, rhythmically and