feat: add sticky marketplace filter bar

[bamiebot-maker]

Summary

• add a reusable StickyFilterBar component for list filtering layouts
• update the marketplace landing page to keep the search filter visible while scrolling
• compress the filter shell on scroll so it stays compact and does not block list content
• keep the layout responsive for both mobile and desktop browsing

Testing

• git diff --check

Notes

• this workspace did not have a dependency install for the repo, so lint/build were not run locally

Closes #31

[drips-wave]

@bamiebot-maker Great news! 🎉 Based on an automated assessment of this PR, the linked Wave issue(s) no longer count against your application limits.

You can now already apply to more issues while waiting for a review of this PR. Keep up the great work! 🚀

Learn more about application limits

[Chucks1093]

@bamiebot-maker fix the merge conflict

[bamiebot-maker]

resolved please merge