Data, geo and palette utilities

Spent the day on the utils. Now it races every live endpoint against a timeout, then falls back to the local samples if anything fails, so the quake, ISS, aurora and air layers don’t each have to roll their own rescue logic. The geo module finally sorts out the lat/lng‑to‑Vector3 mess and generates proper great‑circle arcs with a lift that grows with distance, so the cables and the ISS trail read as actual orbital paths. Palette centralises all the colour constants and adds helpers for quake magnitude shading, aurora probability, and AQI bands.