consolidated some shader uniforms as global

src/mol-canvas3d/passes/postprocessing.ts

src/mol-geo/geometry/base.ts

src/mol-geo/geometry/direct-volume/direct-volume.ts

src/mol-geo/geometry/texture-mesh/texture-mesh.ts

src/mol-gl/_spec/renderer.spec.ts

src/mol-gl/renderable/direct-volume.ts

src/mol-gl/renderable/schema.ts

src/mol-gl/renderer.ts

src/mol-gl/shader/chunks/apply-fog.glsl.ts

src/mol-gl/shader/chunks/common-frag-params.glsl.ts

src/mol-gl/shader/postprocessing.frag.ts

src/mol-plugin-ui/viewport/simple-settings.tsx