Braffolk/fable5-world-demo ? reverse-engineered prompt

Build me a browser based open world forest scene that feels like a tiny playable nature demo. It should run in Chrome with modern GPU rendering, load straight from one seed in the URL, and generate everything procedurally at startup, terrain, trees, plants, lighting, sky, water, fog, and motion, with no imported art assets. I want a big explorable world with walking, sprinting, jumping, and a free fly mode, plus a few saved camera viewpoints and a way to jump to exact camera positions from the URL.

Make it look good in motion, with realistic shadows, clouds, water reflections, wind in the vegetation, and a day night cycle. It should also be built in strict TypeScript and be easy to run locally with a simple dev server. If you need current docs for the rendering API, look them up online and make sure the project works with the latest supported browser features.