Haste v33 - Transparent Sky Compositing (development)

Base: Haste_Shader_V1_1_4_v32_Transparency_Sky_Visibility_Fix_Hotfix_dev.zip
Target: Sodium + Iris shader pipeline.

Problem addressed
Haste builds its final procedural sky and clouds in final.fsh, after translucent water/glass are drawn.
Those translucent surfaces initially blend against the earlier vanilla sky layer. If final.fsh then treats
that pixel only as a foreground surface, the custom sky does not show through consistently and can appear
black or incomplete.

Implementation
- colortex7 captures the pre-final sky from gbuffers_skybasic and the sun/moon from gbuffers_skytextured.
- colortex6 captures the actual translucent surface colour and alpha from gbuffers_water.
- final.fsh identifies translucent pixels with no opaque geometry behind them using depthtex1, then replaces
  only the background contribution with Haste's final sky/cloud result, weighted by surface transmission.
- Existing water composite output is preserved by applying a background-only delta instead of replacing the
  entire final colour. Colortex6/7 flips are disabled in the composite passes so the snapshots remain stable.
- Glass opacity is explicitly assigned per material class so zero-alpha atlas texels cannot accidentally
  suppress the saved translucent layer.
- Existing water shading, SSR/refraction/caustics code, fog controls and profiles are retained.

Validation
ZIP integrity and static source-structure checks are run for this build. This package has not been compiled
inside Iris or tested in Minecraft; runtime compositing order, glass tint, and water appearance still need in-game
verification. The snapshots add two screen-space texture reads in final.fsh; no additional ray marching or draw pass.
