v1.0.1 - UI Polish

V1.0.1 focuses on a visual and experience polish pass for Mumble Voice Lab.\n\nHighlights:\n- Redesigned the live demo into a cleaner, Apple-inspired voice workbench.\n- Added light, dark, and system theme switching with local persistence.\n- Moved advanced parameters, preset JSON, and event preview into a default-collapsed Sound Lab section.\n- Refreshed the online listening showcase with matching visual styling and theme switching.\n- Kept audio generation, deterministic schedules, WAV export, and JSON export behavior unchanged.