Implement proper SMS notification provider with configurable provider abstraction

[nanaf6203-bit]

Problem

SmsService may be a stub without actual SMS provider integration, no abstraction for multiple providers, no rate limiting.

Expected Outcome

Production-ready SMS service with provider abstraction.

Acceptance Criteria

• Provider abstraction interface
• Twilio provider implementation
• AWS SNS provider implementation
• Phone number validation
• Opt-out handling

Files Affected

src/notifications/sms.service.ts, new providers directory

Difficulty

Medium

Estimated Effort

Medium (1 week)

Labels

notifications, enhancement, sms

[Thommyy7]

@Thommyy7 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi, I'd like to take this on.

I'm a full-stack developer with solid experience in modern JavaScript/TypeScript, REST APIs, and frontend frameworks like React. I enjoy working in open source and following existing project conventions.

I've reviewed the issue and I'm confident I can implement a solid solution while following the project's conventions.

Please assign this issue to me, I'd be happy to contribute.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Thommyy7 to this issue.

[Caneryy]

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

Hi, I'd like to work on this issue please.

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

[drips-wave]

Congratulations, @Thommyy7! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

🧑‍💻 @Thommyy7: 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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[drips-wave]

This issue has been completed by @Thommyy7 as part of the Stellar Wave Program's 7th Wave 🥳

😎 @Thommyy7: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here. You can also Leave a review to share your experience working on this issue.

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