feat(submission): add liquid wave button hover effect (#55580)

[anuragbraveboy-sudo]

Pull Request Description

This PR resolves #55580 by implementing a Liquid Wave Button hover effect component (.ease-btn-liquid) in pure CSS.

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Type of Change

• ✨ New animation / hover effect
• 🧩 New component
• 📝 Documentation improvement
• 🐛 Bug fix in an existing submission
• Other (describe below)

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Submission Checklist

⚠️ PRs that fail this checklist will be closed without review.

• All changes are inside submissions/examples/your-feature-name/
• Includes demo.html — self-contained, opens in browser with no server
• Includes style.css — raw CSS for the proposed feature
• Includes README.md — what it does, how to use it, why it fits EaseMotion CSS
• No changes to core/
• No changes to components/
• One feature per PR (no bundled unrelated changes)

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Feature Description

What does this add?

Adds a new button variant with a smooth, pure CSS liquid/wave rising animation on hover.

How does a developer use it?

<button class="ease-btn ease-btn-liquid">Liquid Wave 🌊</button>

[SAPTARSHI-coder]

✅ Submission Validation Passed!

Great job! All required files are present and valid.

📁 Folder: submissions/examples/liquid-wave-button-55580

Files found:

• ✅ demo.html
• ✅ style.css
• ✅ README.md

🚀 Next Steps:

• A maintainer will review your PR
• Respond to any feedback if requested
• Once approved, your contribution will be merged!

Thank you for contributing to EaseMotion CSS! 🎉

[github-actions]

🎉 Congratulations on your PR merge, @anuragbraveboy-sudo! 🚀

Thank you so much for your valuable contribution to EaseMotion CSS! Your code is now merged into the main branch.

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[github-actions]

🎉 Pull Request Integrated!

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🎮 Join our Discord Server!
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