🧪 Magnetosphere Shield (2D)

This 2D companion drives the same dipole-compression physics as the 3D version through a plain top-down canvas view: the magnetopause standoff distance shrinks as solar wind pressure rises and grows as field strength rises, wind particles bend around the boundary instead of passing through, and any that slip toward the polar cusps light up the aurora oval — the same behaviour, easier to read as a flat cross-section.