Remove mock protocol APY sources; implement real protocol rate fetchers

[robertocarlous]

Problem

Protocol scanning uses mocked APY/TVL values (src/agent/scanner.ts). This makes the agent's decisions unreliable and invalidates production claims.

Acceptance criteria

• Replace mock fetchers with real data sources for each supported protocol (Blend, Stellar DEX pools, Luma)
• Add timeouts, retries, and circuit breaker behavior per upstream
• Persist raw source data + computed APY in ProtocolRate for auditability
• Add integration tests that stub upstream HTTP responses
• Add metrics: fetch duration, failures per source, stale-rate detection

Priority

P0 / Critical

[anoncon]

Hello,

I’m a developer with 4 years of hands-on experience working on production-grade systems and contributing to collaborative, open-source environments. I’ve carefully read through this issue and fully understand the problem it addresses, the expected outcomes, and the constraints outlined in the acceptance criteria.

[BernardOnuh]

Hi! I’m a full-stack developer with a strong blockchain background. I’d love to handle this issue and can deliver a clean, reliable solution. Kindly assign it to me.

[BernardOnuh]

Hi! I’m a full-stack developer with a strong blockchain background. I’d love to handle this issue and can deliver a clean, reliable solution. Kindly assign it to me.

[grantfox-oss]

🦊 GrantFox — @BernardOnuh has been assigned to this issue as part of the Official Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #157)
2. Your PR will be reviewed by the Neurowealth maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign campaign!

@BernardOnuh's PR #183 was approved and merged by @robertocarlous.

🏆 @BernardOnuh: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (48 total points). Track your full progress on GrantFox.

👏 Great work, @BernardOnuh! Keep contributing to Neurowealth.