Clean up object URL after extracting skin sprites

After sprites are extracted from the image via getSpriteUrisFromImg
(which draws to canvas and creates data URLs), the original image and
its object URL are no longer needed. Clean up the object URL at this
point to prevent memory leaks.

This only affects the fallback path (HTMLImageElement) since ImageBitmap
doesn't have a src property and doesn't use object URLs.

Author: claude

packages/webamp/js/skinParserUtils.ts

@@ -56,10 +56,7 @@ export async function getFileFromZip(
 }
 
 function fallbackGetImgFromBlob(blob: Blob): Promise<HTMLImageElement> {
-  // Note: We cannot revoke the object URL here because the returned image
-  // element needs the URL to remain valid for its lifetime. This is an
-  // acceptable small leak since skin images are loaded infrequently and
-  // the primary path uses createImageBitmap which doesn't have this issue.
+  // Create object URL that will be cleaned up after the image is used
   return Utils.imgFromUrl(URL.createObjectURL(blob));
 }
 
@@ -129,7 +126,17 @@ export async function getSpriteUrisFromFilename(
   if (img == null) {
     return {};
   }
-  return getSpriteUrisFromImg(img, SKIN_SPRITES[fileName]);
+
+  // Extract sprites from the image
+  const sprites = getSpriteUrisFromImg(img, SKIN_SPRITES[fileName]);
+
+  // Clean up object URL if the image is an HTMLImageElement with a blob URL
+  // (ImageBitmap doesn't have a src property, so this only affects the fallback path)
+  if (img instanceof HTMLImageElement && img.src.startsWith("blob:")) {
+    URL.revokeObjectURL(img.src);
+  }
+
+  return sprites;
 }
 
 // https://docs.microsoft.com/en-us/windows/win32/xaudio2/resource-interchange-file-format--riff-