Prepare Chrome Web Store screenshot and listing assets

[Najariya]

Goal

Prepare the visual and text assets needed before any Chrome Web Store submission.

Assets

• 3-5 screenshots at the required dimensions
• Short listing summary
• Detailed listing description
• Permission justification for <all_urls>
• Privacy policy URL confirmation

Done when

• Assets are listed in RELEASE_CHECKLIST.md
• Screenshots are stored in a clear repo folder or attached to a release planning note
• The listing copy is ready for manual review before submission