fix(image): preserve raster brightness

src/scene/pipeline/image_gpu.rs

@@ -223,7 +223,7 @@ impl ImageGpu {
                     mip_level_count: 1,
                     sample_count: 1,
                     dimension: wgpu::TextureDimension::D2,
-                    format: wgpu::TextureFormat::Rgba8UnormSrgb,
+                    format: wgpu::TextureFormat::Rgba8Unorm,
                     usage: wgpu::TextureUsages::TEXTURE_BINDING
                         | wgpu::TextureUsages::COPY_DST,
                     view_formats: &[],