Add test coverage for the rate limiter, pause guard, and 503 behaviour

[mikewheeleer]

Test the rate limiter and pause-guard middleware

Description

The in-process rate limiter (60 req/IP/60s) and the pause guard (503 on writes when paused, with /admin/unpause exempted) in src/index.ts are core protective middleware, yet src/health.test.ts only checks one pause/unpause happy path and never exercises the limiter's 429. This issue adds focused coverage.

Requirements and context

• Repository scope: Agentpay-Org/Agentpay-backend only.
• Test that exceeding the limit yields 429 rate_limited with a Retry-After header and requestId, and that GET requests below the limit pass.
• Test the pause guard: writes return 503 service_paused, GET/HEAD/OPTIONS still pass, and POST /api/v1/admin/unpause is exempt.
• Test that GET /api/v1/admin/status reflects the current pause flag.
• Keep tests deterministic (no real sleeping); reset state between cases as needed.

Suggested execution

• Fork the repo and create a branch
• git checkout -b test/testing-14-ratelimit-pause
• Implement changes
  • Write comprehensive tests in: new src/middleware.test.ts using supertest.
  • Write code in: no production change expected; if the limiter is hard to test deterministically, note the limitation in the PR.
  • Add documentation: none beyond test descriptions.
  • Add clear test titles.
  • Validate security assumptions: confirm the limiter and pause guard cannot be bypassed via method casing or path tricks.
• Test and commit

Test and commit

• Run npm run build, npm test, and npm run lint.
• Cover edge cases: exactly at the limit, just over, unpause recovery, status reflects flag.
• Include the full npm test output in the PR description.

Example commit message

test: cover rate limiter and pause-guard middleware

Guidelines

• Minimum 95 percent test coverage for impacted modules.
• Clear, reviewer-focused documentation.
• Timeframe: 96 hours.

Community & contribution rewards

• 💬 Join the AgentPay community on Discord for questions, reviews, and faster merges: https://discord.gg/eXvRKkgcv
• ⭐ This is a GrantFox OSS / Official Campaign task and may be rewarded. When your PR is merged you'll be prompted to rate the project — if this issue and the maintainers helped you ship, we'd be grateful for a 5-star rating. Clear questions in Discord and tidy, well-tested PRs are the fastest path to a merge and a reward.

[BojayL]

/claim

[BojayL]

/attempt #71

[gloskull]

Hello, I have 4 years of experience delivering solutions for projects like this, covering backend, frontend, and smart contract development. After carefully reviewing your requirements, I have a clear understanding of the task and am confident in my ability to deliver a clean, efficient, and thoroughly tested solution on time. I prioritize code quality, maintainability, and industry best practices throughout the development process. My PR will be submitted in under 10hours.

[pq198363-ops]

/claim