New prompt: Fluid simulation

Fluid simulation asks a model for a real-time, mouse-driven WebGL fluid solver in a single HTML file: advection, pressure, the works. It is the most demanding prompt we run, and the spread is wide.

A handful of models produced a genuinely convincing dye-and-velocity field; others returned a black canvas because a shader failed to compile. The strip below runs from clean to dead so you can see exactly where each one lands.