I want to build a small terrain viewer: the camera travels along a predefined route, hugging the ground, and the scene is a grassland that appears boundless. Under soft, overcast diffuse lighting, the grass blades should sway naturally; the system needs to accumulate flight distance in real time based on speed, and the wind sound should vary with speed. Technically, React Three Fiber can be used; grass lighting and sway should be implemented in GLSL, and wind sound synthesized with the Web Audio API. Please design an overall solution according to these goals and provide the core implementation approach.