Centralize API Error Handling

[Abd-Standard]

Description
Standardize API error responses across all backend services.

Acceptance Criteria
All endpoints use centralized error handling.
Responses follow a consistent format.
Existing functionality is preserved.

[supreme2580]

@supreme2580 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi maintainer, can I be assigned to this issue?

ℹ️ Repo Maintainers: To accept this application, review their application or assign @supreme2580 to this issue.

[Fayvor22]

@Fayvor22 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I would love to work on this issue and provide implementation that will resolve it

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Fayvor22 to this issue.

[Jessepriase]

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

I would like to work on this issue

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

[drips-wave]

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

🧑‍💻 @Jessepriase: 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 🌊

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox!

@Jessepriase's PR #591 was approved and merged by @Abd-Standard.

🏆 @Jessepriase: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (446 total points). Track your full progress on GrantFox.

👏 Great work, @Jessepriase! Keep contributing to Core-Foundry.