[Feature][Mobile] Implement NFC Tag Writing Support to share DevCards

[JavaProgswing]

Problem

DevCard aims to be the ultimate frictionless developer profile exchange platform. While we currently support QR codes and web links, many modern digital business cards use NFC (Near Field Communication) for a true "one tap" experience.

Currently, the backend already has the /api/nfc/payload endpoint implemented (which safely returns the NDEF URI payload for a user's DevCard). However, the mobile app (apps/mobile) completely lacks the UI and functionality to write this payload to a physical NFC tag. Without this mobile integration, the backend endpoint is orphaned and users cannot create their own physical tap-to-share DevCards.

Current Behaviour

• The backend successfully serves NDEF URI payloads via GET /api/nfc/payload.
• The React Native mobile app has no NFC dependencies (like react-native-nfc-manager) and no UI to write to NFC tags.
• Users must rely solely on QR codes or manual links, missing out on the one-tap NFC sharing experience.

Expected Behaviour

• The mobile app should include a "Write to NFC Card" button on the Card Share or Settings screen.
• Tapping the button should fetch the payload from /api/nfc/payload.
• The app should prompt the user to "Hold your phone near an NFC tag" and use react-native-nfc-manager to write the NDEF URI payload to the tag.
• Once successfully written, tapping the physical NFC tag with any modern smartphone should instantly open the user's DevCard profile in the browser.

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I would love to work on this as part of GSSoC '26. Kindly consider assigning this to me.

[JavaProgswing]

I would love to work on this as part of GSSoC '26. Kindly consider assigning this to me.