chore(icon): update icon image and add entry point instructions (#157)

* chore(icon): update icon image and add entry point instructions

- Replace the existing icon.png with a new version
- Add comments in index_old.tsx to guide renaming for extension development

* chore(icon): replace icon image with updated version

* chore(icon): replace icon.png with icon.jpg

- Remove old icon.png and add new icon.jpg for better quality

Author: harryisfish

assets/icon.jpg

@@ -1,3 +1,6 @@
+// You can rename this file to index.tsx to use this file as the entry point
+// Then you can develop the extension option page as UI
+
 import '~style.css';
 import React, { useState } from 'react';
 import { HeroUIProvider } from '@heroui/react';