Add tests for the error and not-found app boundary pages

[mikewheeleer]

Test the error boundary reset and the not-found page

Description

src/app/error.tsx is the route error boundary (renders an error heading and a "Try again" button bound to reset) and src/app/not-found.tsx renders the 404 with a back-home link — neither has a test, so a regression in the reset wiring or the 404 link would ship unnoticed. This issue covers both.

Requirements and context

• Repository scope: Agentpay-Org/Agentpay-frontend only.
• error.tsx: assert the error message renders, clicking "Try again" calls the reset prop, and the recovery affordance is reachable.
• not-found.tsx: assert the 404 heading and a link back to / render.
• If error.tsx does not yet announce its message via role="alert", add it and assert it (small a11y fix bundled with the test).

Suggested execution

• Fork the repo and create a branch
• git checkout -b test/testing-error-notfound
• Implement changes
  • Write code in: add role="alert" to the error message in src/app/error.tsx if missing.
  • Write comprehensive tests in: create src/app/error.test.tsx and src/app/not-found.test.tsx.
  • Add documentation: none beyond test descriptions.
  • Validate the reset callback fires exactly once per click.
• Test and commit

Test and commit

• Run npm run lint, npm run typecheck, npm test, and npm run build.
• Cover edge cases: error with a digest, empty message, and the 404 link target.
• Include the npm test output and coverage for both files.

Example commit message

test(app): cover error boundary reset and not-found page

Guidelines

• Minimum 95 percent test coverage for both files.
• 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.

[YfengJ]

Hi maintainers, I would like to apply for this issue if it is still available.

If assigned, I would keep the work scoped to test coverage for src/app/error.tsx and src/app/not-found.tsx: assert the error UI renders, add/assert role="alert" if missing, verify the reset callback fires exactly once per click, and cover the 404 heading plus the / home link.

I would run npm run lint, npm run typecheck, npm test, and npm run build, then include the relevant validation output in the PR.

Thanks!

[GBOYEE]

I'll take this up — writing tests for the error boundary and not-found page. Starting shortly.

[GBOYEE]

#214 fixes the broken imports on main that are causing CI to fail for #155 and #151 — this needs to be merged first so those PRs can pass build-test.