Wonderbox-inspired lighting overhaul across all 3 pixel shaders:
- Hemisphere ambient (sky blue above, warm brown below) replaces flat ambient
- RT shadows lerp toward blue-violet tint instead of plain darkening (factor 0.55)
- Rim light (fresnel) with warm golden color on silhouettes (30% on vegetation)
- Soft exponential tone mapping + saturation boost in final post-process pass
- CB parameters for all lighting values (skyAmbient, groundAmbient, shadowTint, etc.)
- Fog color/density centralized from CB instead of hardcoded per-shader
- Screenshot mode (CLI "screenshot"): fixed camera, AO convergence, auto-capture
- AO noise stability: world-space hash using voxel center + tangent-axis frac position
- AO distance-weighted falloff: continuous occlusion values instead of binary hit/miss
- 8 cosine-weighted hemisphere rays per pixel (inline ray queries, SM 6.5)
- Distance-weighted AO: quadratic falloff (1-hitT/aoRadius)² instead of binary hit/miss
- World-space hash seed: voxel coord + tangent-plane frac position (stable, no flicker)
- Bilateral blur pipeline: 2-pass separable (H+V), radius 6, depth+normal edge-stopping
- 4-pass dispatch: shadow+rawAO → blur H → blur V → apply
- AO written to separate R8_UNORM texture, blurred, then applied to color buffer
- Debug mode (F5 x3): grayscale AO visualization
