Add end-to-end API test suite using Supertest

[Abdulazeem-code]

Description

Current tests are mostly unit tests or test isolated modules. There are no end-to-end tests that verify the full request lifecycle through middleware, validation, and response formatting.

Proposed Solution

Create an E2E test suite using Supertest that boots the Express app and tests critical flows: registration, federation lookup, webhook CRUD, and admin operations.

Acceptance Criteria

• E2E test file created covering registration flow
• Federation name and ID lookups tested
• Webhook create/list/delete flow tested
• Admin block and export flows tested

Suggested Implementation Areas

tests/e2e/ (new directory), tests/e2e/registration.e2e.test.js, tests/e2e/federation.e2e.test.js

Impact

Catches integration bugs that unit tests miss, especially middleware ordering and error handler behavior.

[attyolu]

@attyolu has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Good evening Maintainer. Please assign this issue to me. I'm begging

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

[Peolite1]

@Peolite1 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

i would love to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Peolite1 to this issue.

[drips-wave]

Congratulations, @Peolite1! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

🧑‍💻 @Peolite1: 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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