“Don’t stop,” the melody whispered — not command but invitation. Each refrain braided with a digital chirp: 012avi — a filename, a code, a breadcrumb left by a street artist who painted foxes on utility boxes. The foxes’ eyes were tiny QR squares; scan them and a hidden clip titled 012avi unfurled: a grainy, golden recording of a city at dawn, sunlight pooling like honey in puddles.