Add mutation testing with Stryker for frontend and backend

[Smartdevs17]

Description

Standard coverage misses untested code paths. Implement mutation testing to evaluate and improve test quality.

Acceptance Criteria

• Stryker configuration for TypeScript/React Native
• Mutation score gate (>75%)
• Survived mutant analysis and test improvement
• CI integration with PR comments
• Historical mutation score tracking
• Incremental mutation testing for performance

Technical Scope

• stryker.conf.json
• .github/workflows/
• Edge: equivalent mutants, mutation testing time, CI resource constraints

[MavDavis]

@MavDavis has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi segun, na me ooo 😂
Can I take this?

ℹ️ Repo Maintainers: To accept this application, review their application or assign @MavDavis to this issue.

[drips-wave]

Congratulations, @MavDavis! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @MavDavis: 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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