Fix: keep contact shadows visible at low camera angles

Contact shadows under the tank disappeared when the camera orbited low enough to look up at it. The shadow plane and the ground disc are both transparent and centred on the origin, so three.js sorts them by camera depth. Looking upward flips that order, and because the shadow doesn't write depth, the ground disc was drawn over it.

- Gave `ContactShadows` a `renderOrder` of 1 so it always renders after the ground disc

Fixes #299

packages/website/src/components/Tankopedia/HeroSection/components/TankSandbox/components/Lighting.tsx

@@ -82,6 +82,7 @@ export function Lighting({ hasPbr }: Props) {
         blur={2 ** 1}
         resolution={2 ** 9}
         depthWrite={false}
+        renderOrder={1}
       />
 
       {animate && (