[TESTING] Write API integration tests for auth endpoints

[dev-fatima-24]

Priority: critical

Description

The SEP-10 challenge and verify endpoints need integration tests that exercise the full request/response cycle with a mocked Stellar SDK.

Acceptance Criteria

• Test: POST /v1/auth/sep10 with valid public key returns a challenge transaction
• Test: POST /v1/auth/sep10 with missing public key returns 400
• Test: POST /v1/auth/verify with valid signed tx returns a JWT
• Test: POST /v1/auth/verify with invalid signature returns 401
• Test: POST /v1/auth/verify with expired challenge returns 401

[Tboy123-emm]

@Tboy123-emm has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

hello please i'd like to work on this issues

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Tboy123-emm to this issue.

[drips-wave]

Congratulations, @Tboy123-emm! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @Tboy123-emm: 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

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