feat: add Checkout Pilot hackathon submission

[mosesfawole]

Summary

Adds Checkout Pilot as an MCP hackathon submission.

Capability

A hosted payment-link demo for small merchants. It creates referenceable payment requests and reads settlement status; demo mode never moves money. Live mode uses only the server-side Moove Receive payment-link API adapter.

Evidence

• Source: https://github.com/mosesfawole/checkout-pilot
• Review commit: 1c4740857de59595f8d2bb4501f6e44d00a160f4
• API: https://checkout-pilot.onrender.com
• Health: https://checkout-pilot.onrender.com/health
• Deployment proof: https://checkout-pilot.onrender.com/.well-known/xagent-verification.json
• Offline and online validate:submission pass.

Testing

npm test passes all 9 project tests.

[github-actions]

Submission received — #57

Thank you for submitting to the current X-Agent MCP Hackathon. We have received your pull request.

This is a receipt only. It does not confirm eligibility, completeness, technical approval, a judging result, or an award. Passing automated checks or merging code for archival purposes does not, by itself, mean the entry has passed review or won a prize.

Please include the complete source for the submitted capability in this repository under submissions/mcp-hackathon/<slug>/source/, with dependency files, configuration examples, and reproducible setup/build instructions. An external repository link alone is not sufficient. The official copy is intended to remain available if the original repository later becomes unavailable. Do not include secrets, credentials, or private user data; clearly disclose external and private-service dependencies.

The automated checks report technical checks separately. A workflow failure is not a judging decision. Keep updates in this PR while submissions remain open, and keep the documented source version and deployment evidence consistent.

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