Backend: Complete compliance velocity check implementation

[ONEONUORA]

Problem

detect_high_velocity is defined but threshold logic isn't fully implemented.

Impact

• Incomplete compliance monitoring
• Regulatory risk
• Potential violations undetected

Solution

Complete velocity check implementation with proper threshold logic.

Files to Modify

• backend/src/compliance.rs

Priority

High - Compliance requirement

[Belzabeem]

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

If assigned, I'll complete the detect_high_velocity logic in backend/src/compliance.rs with proper threshold evaluation, add tests covering both passing and violation scenarios, and ensure no potential violations slip through undetected

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

[ikemHood]

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

I can get this done asap

ETA: 2hrs
Please assign

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

[drips-wave]

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

🧑‍💻 @Belzabeem: 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.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊