MessageLinkEmbeds: prefer attachment proxyURL (#4543)

src/plugins/messageLinkEmbeds/index.tsx

@@ -356,7 +356,7 @@ function AutomodEmbedAccessory(props: MessageEmbedProps): JSX.Element | null {
                     const { width, height } = computeWidthAndHeight(a.width, a.height);
                     return (
                         <div key={idx}>
-                            <img src={a.url} width={width} height={height} />
+                            <img src={a.proxyURL ?? a.url} width={width} height={height} />
                         </div>
                     );
                 })}