Add 7 shaders to the stylize module, exposed through the existing
Style* runtime and Squirrel API (no new module or bindings):
- Mesh materials (reuse mesh3d_toon.vert): rim light, dissolve,
hologram, snow accumulation.
- Post passes: vignette, chromatic aberration, film grain.
Original GLSL implementations of common techniques, not verbatim
copies (see docs/dev/ported-material-shaders.md for licensing).
Adds EffectShaders.{h,cpp} with param tables + uniform binding +
shader creation, wired via delegation from StyleShaders.cpp, plus
SPIR-V embeds and per-module tests (test/stylize_effects.cpp).
西风逍遥游