fix(N8AO): use the EffectComposer's camera and scene

[RaphaelFakhri]

Summary

<N8AO> read camera and scene from useThree(), so it ignored the camera and scene props of <EffectComposer>. Every other component (LensFlare, Outline, SelectiveBloom, GodRays, DepthOfField, useDepthPicking) reads them from EffectComposerContext.

N8AOPostPass uses its camera for all AO math (projection and view matrices, depth reconstruction) and renders its scene with it. When the composer renders a different camera than the canvas default, the depth buffer comes from one camera and the AO is reconstructed with another, so the occlusion is misplaced. Switching the composer's camera also left N8AO on the old one.

<EffectComposer camera={otherCamera}>
  <N8AO />
</EffectComposer>

Changes

• src/passes/N8AO.tsx: take camera and scene from EffectComposerContext. invalidate still comes from useThree.
• src/tests/N8AO.test.tsx: add a test that checks the pass gets the composer's camera and scene, and follows a camera change.

Testing

• pnpm vitest run src/tests/N8AO.test.tsx: the new test fails without the fix (1 failed, 3 passed) and passes with it (4 passed).
• pnpm test: 29 files, 221 tests passed.
• pnpm typecheck, pnpm eslint:ci and Prettier are clean.