noisefactorllc/visualize ? reverse-engineered prompt

Build me a browser based music visualizer and VJ gig player that runs right in the browser, with no install for the audience.

It should have two decks, a crossfader between them, live shader visuals that react to audio, MIDI control for mixing and effects, and an auto VJ mode that can swap visuals on the beat. I also want scenes so I can save and recall full set states, plus session recovery so a refresh does not lose everything. Include recording of the main canvas, a fullscreen mode, and a separate output window for a projector or second screen.

Make it feel polished and usable during a live set, with keyboard shortcuts, settings for audio input, and a clean library of visual programs. If you need current docs for any browser APIs or shader stuff, look them up online. Keep it simple to run locally too, ideally just open it in the browser after starting a local server.