🛰️ Rotating Space Station — 2D Inertial vs Rotating Frame, Coriolis Drop and Apparent Gravity

2D companion of the rotating space station: a ball dropped or thrown inside the ring seen from the inertial frame (straight line) and the rotating frame (Coriolis curve), apparent gravity against radius, and spin rate needed for 1 g, with in-page checks against the exact inertial solution.