UnitedShader port target: Minecraft Java 1.20.5 - 1.20.6
Compatible target versions: 1.20.5 and 1.20.6

This port preserves the existing UnitedShader rendering/effect pipeline.
1.20.5/1.20.6 did not require new block-property mappings for the shader's
existing terrain/material classifications, so the 1.20.x mappings are retained.
Targeted compatibility: Iris / OptiFine-style shader loading.
