Enhancement/base64 to image

[afzalzain]

📝 Description

This PR adds the core Base64 to Image conversion functionality along with a Jest-based automated test to verify the conversion flow.
The implementation converts Base64 input into an image preview, enables image download, and ensures correctness through automated testing using jsdom.

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🎯 Type of Change

• 🆕 New tool added
• 🐛 Bug fix
• 📚 Documentation update
• 🎨 UI/UX improvement
• ⚡ Performance optimization
• 🔧 Code refactoring
• 🧪 Test addition
• 🚀 Feature enhancement

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🛠️ Changes Made

• Implemented Base64 to Image conversion logic using JavaScript
• Added image preview rendering from Base64 input
• Enabled image download with correct file type and name
• Added Jest configuration with jsdom environment
• Created automated Jest test to validate Base64 → Image conversion

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🧪 Testing

• ✅ Tested on Chrome
• ✅ Tested on Firefox
• ✅ Tested on Safari
• ✅ Tested on Edge
• ✅ Tested on mobile devices
• ✅ No console errors
• ✅ Base64 conversion works as expected
• ✅ Automated Jest test passes successfully

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📸 Demo Video

demo-video.mp4

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🔗 Related Issues

Related to Base64 Image conversion feature and test coverage.

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📱 Browser Testing

• Chrome (latest)
• Firefox (latest)
• Safari (latest)
• Edge (latest)
• Mobile Chrome
• Mobile Safari

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📋 Checklist

• My code follows the project's style guidelines
• I have performed a self-review of my own code
• I have commented the conversion logic where necessary
• I have made corresponding documentation changes
• My changes generate no new warnings or errors
• I have added tests that prove the feature works
• New and existing unit tests pass locally
• Any dependent changes have been merged

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🎨 UI/UX Changes

• Design updated
• No major UI changes (logic-focused update)
• Error handling is user-friendly

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⚡ Performance Impact

• No performance regression
• Efficient Base64 decoding and Blob handling
• Minimal bundle size impact

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🔒 Security Considerations

• No security vulnerabilities introduced
• Input validation for Base64 data implemented
• No sensitive data exposed

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📚 Documentation

• README updated (optional)
• Code comments added for conversion logic
• API documentation updated

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🎯 Additional Notes

This PR strengthens the Base64 to Image tool by combining functional implementation with automated testing, improving reliability and maintainability.

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🚀 Deployment Notes

No deployment changes required.

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👥 Reviewers

@echobash/devdunia-maintainers

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🙏 Thank you for reviewing this PR!
This contribution improves both functionality and test coverage for DevDunia 🚀