fontTextureSlot/fontSamplerSlot are push constants, hence provably
dynamically uniform. Wrapping them in nonuniformEXT forced the
per-invocation divergent-descriptor path and blocked hoisting the
uniform descriptor load out of the per-pixel glyph loop.
Removing the decoration is zero correctness risk — it is purely a
read-index hint. Not applied to ui-images.comp.glsl, whose slots come
from an SSBO load the compiler cannot prove uniform.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
