Sportinger/MasterSelects ? reverse-engineered prompt

Build me a local first media editor that runs right in the browser with no backend. I want it to feel like a real timeline based editor where I can drop in video, audio, images, vector animations, and 3D assets, then scrub, trim, layer, and preview everything smoothly. It should support common video and audio files, plus Lottie and Rive animations, OBJ and glTF models, and gaussian splat style 3D media.

Please make the editing experience GPU powered and responsive, with real time playback, effects, transitions, blend modes, and basic audio tools like waveform view, volume control, and stem separation if possible. I also want export options for common video and image formats, plus an interchange export for professional editors. Keep it polished and modern, with a clean dark interface, timeline panels, media library, and preview area. If you need to, look up current browser and WebGPU docs online while building it.