BT- Spectral Fog: Next Gen Volumetric Fog for URP

BT-Spectral Fog delivers temporally-stable volumetric fog for URP using quarter-resolution raymarching (QuadMarch) with temporal stabilization via motion-vector reprojection (GhostGuard) and depth-aware blur (EdgeWeave). It supports sun and point light scattering, Adaptive Probe Volume integration, local fog volumes (PocketFog), animated density noise, one-click height auto-fit (HeightSync), a clean tabbed inspector, dual render path (full Unity 6 Render Graph with compatibility mode), and scales from VR/mobile to desktop fidelity for both perspective and orthographic cameras.