Function extract_chromatic_phase_textures 

pub fn extract_chromatic_phase_textures(
    reader: MessageReader<'_, '_, AssetEvent<Image>>,
    images: Res<'_, Assets<Image>>,
    scattering_media: ResMut<'_, Assets<ScatteringMedium>>,
)

Resolves PhaseFunction::ChromaticTexture to PhaseFunction::ChromaticCurve when the image loads.