Revamp white paper — plain language, drop the false formalism

Replace the 1,066-line theorem-heavy paper with a 228-line version written for engineers and AI practitioners. Cuts all LaTeX proofs, the circular existence-proof structure, and the Bitcoin tangent. Keeps the concrete MIDI examples, the 21-dimension model, the plugin protocol, and the AI-agents argument — the parts that actually land. New tagline: "Git versions files. Muse versions meaning."