docs(cursor): explain image decoding and Retina sampling

flutter/lib/models/model.dart

@@ -2995,7 +2995,9 @@ class PredefinedCursor {
 
       () async {
         _image?.dispose();
-        // PNG stores straight alpha; let the codec prepare the pixels for ui.Image.
+        // Native registration uses this ui.Image. The RGBA bytes from img2 are
+        // straight alpha, but PixelFormat.rgba8888 requires premultiplied alpha.
+        // Decode the PNG directly to preserve translucent cursor colors.
         final codec = await ui.instantiateImageCodec(pngBytes);
         final ui.Image nativeImage;
         try {

src/platform/macos.rs

@@ -638,6 +638,9 @@ fn unsafe_get_cursor_data(hcursor: u64) -> ResultType<CursorData> {
         if hcursor != hcursor2 {
             bail!("cursor changed");
         }
+        // NSImage.size is in points; using it as bitmap dimensions can crop Retina
+        // artwork. Render the full image and convert its hotspot to pixels;
+        // keep the existing 1x sampling path below.
         if scale > 1.0 {
             return cursor::data(c, hcursor, scale);
         }