[LOW] AI service circuit breaker has no metrics export

[kilodesodiq-arch]

Engineering Gap

app/ai-service/services/circuit_breaker.py implements circuit breaker pattern but does not export Prometheus metrics for breaker state transitions, failure counts, or recovery events.

Codebase Evidence

• app/ai-service/services/circuit_breaker.py: Circuit breaker implementation
• app/ai-service/metrics.py: Prometheus metrics exist but no circuit breaker metrics

Risk Profile

Circuit breaker tripping undetected until service degradation noticed by users.

Remediation Strategy

Add Prometheus gauge for circuit state (CLOSED/OPEN/HALF_OPEN). Add counter for failure count. Add histogram for recovery time.

Success Conditions

• Circuit state gauge exported
• Failure counter exported
• Recovery time histogram exported

Change Surface

Files: circuit_breaker.py, metrics.py

Security Review

No security impact.

Completion Checklist

• Implementation completed
• Peer reviewed
• Tests passing
• Ready for merge

[Moonwalker-rgb]

Hi Maintainer,

I’d love to work on this issue. I’ve reviewed the requirements and believe I can implement the solution according to the project’s guidelines and best practices.

If the issue is available, I’d be happy to take ownership and submit a PR for review.

Thank you for your consideration.

[grantfox-oss]

🦊 GrantFox — @Moonwalker-rgb 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 #134)
2. Your PR will be reviewed by the ChainForgee 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!

@Moonwalker-rgb's PR #194 was approved and merged by @kilodesodiq-arch.

🏆 @Moonwalker-rgb: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (226 total points). Track your full progress on GrantFox.

👏 Great work, @Moonwalker-rgb! Keep contributing to ChainForgee.