HASTE SHADER V1.1.8.9 — RAIN RENDERING FIX

Based on V1.1.8.8 Grass Root-Pinned Wind.

Changes:
- Removed custom object-space rain vertex shear. Vanilla weather mesh positions
  are preserved to prevent slanted/fragmented rain streaks.
- Weather texture coordinates now respect gl_TextureMatrix[0], including the
  engine's weather texture transform/animation.
- Vanilla per-vertex weather tint and alpha are preserved in the fragment pass.
- Reduced default rain/snow brightening to avoid over-emphasized speckling.
- Retained the existing FXAA and depth-aware sky silhouette protection, along
  with the grass root-pinning, Distant Horizons water fix, bloom and other effects.

Validation: ZIP integrity, shader entry existence, and basic source/preprocessor
checks passed. This build has not been compiled or rendered inside Minecraft.
