Support transparent screenshot surfaces

crates/obscura-js/src/lib.rs

@@ -14,6 +14,7 @@ pub use v8_flags::set_v8_flags;
 #[cfg(feature = "render")]
 pub use obscura_render::{
     screenshot_png, screenshot_png_scrolled, screenshot_png_scrolled_at_animation_time,
+    screenshot_png_scrolled_at_animation_time_with_surface_color,
     validate_capture_region, AnimationSample, AnimationSampleMode, AnimationSampleTime,
     CaptureError, CaptureRegion, ImageRequestProfile,
     MAX_CAPTURE_DIMENSION, MAX_CAPTURE_PIXELS,