feat(mobile): add quick copy profile link button in scan screen

[kavin553]

Summary

Adds a quick “Copy Profile Link” button near the QR sharing section in the mobile Scan screen to improve profile sharing accessibility and usability.

Closes #276

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Type of Change

• Bug fix
• New feature
• Refactor (no functional change)
• UI / Design change
• Tests only
• Documentation
• Infrastructure / DevOps
• Security

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What Changed

• Added a “Copy Profile Link” button below the QR share section in "ScanScreen.tsx"
• Added clipboard support for copying DevCard profile links instantly
• Added new styles for the copy button to match existing app UI

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How to Test

1. Run the mobile app locally
2. Open the Scan Screen
3. Tap the “Copy Profile Link” button and verify the profile URL copies successfully

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Checklist

• My code follows the project's coding style ("pnpm -r run lint" passes).
• TypeScript compiles without errors ("pnpm -r run typecheck").
• I have added or updated tests for the changes I made.
• All tests pass locally ("pnpm -r run test").
• I have updated documentation where necessary.
• No new "console.log" or debug statements left in the code.
• Breaking changes are documented in this PR description.

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Screenshots / Recordings

Added a new “Copy Profile Link” button below the QR code share section in the mobile Scan screen.

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Additional Context

This improves quick sharing experience for mobile users without requiring QR scanning.

[kavin553]

Hi maintainers 👋

Implemented the quick “Copy Profile Link” feature for the mobile Scan screen.

Changes included:

• Added copy profile link button near QR section
• Integrated clipboard functionality
• Added matching UI styles for mobile experience

Please review the changes. Thank you 🚀

[Prince2301p]

Hi,
I would like to work on resolving this issue. Please assign it to me. I’m a participant in GSSoC 2026 and would be happy to contribute.
Looking forward to collaborating with you.