Fix undefined scanner handlers and state in MobileNavigation

[RUKAYAT-CODER]

Overview
In src/components/mobile/MobileNavigation.tsx the Scan button and scanner reference openScanner (line 187), isScannerOpen, and closeScanner (line 195) which are never declared in the component, so the scanner cannot open and the code fails type-check/runtime. Declare the scanner state and handlers.

[Adeyemi-cmd]

@Adeyemi-cmd has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Can I please work on this

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[chidii]

@chidii has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello Maintainer, I've reviewed this issue thoroughly and I'm well positioned to resolve it — experienced across the relevant stack and comfortable navigating the existing codebase. Ready to start right away.

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[akinboyewaSamson]

@akinboyewaSamson has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi Maintainer,

I would love to be assigned to this issue.

I’m a Full-Stack Developer and I also actively explore blockchain development and smart contracts, which has strengthened my problem-solving skills and attention to code quality.

After reviewing the issue, I believe I can contribute effectively and deliver a well-tested solution within the expected standards of the project.

ETA: 6 hours

Thank you for your consideration.

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[drips-wave]

Congratulations, @Adeyemi-cmd! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

🧑‍💻 @Adeyemi-cmd: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

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