feat: add eos debug repo-health command for repository health checks

[CodeMonkeyCybersecurity]

Summary

Wire the new pkg/repohealth package into an eos debug repo-health command that developers and CI can use to diagnose repository issues.

Proposed Features

• eos debug repo-health - Full ownership audit with report
• eos debug repo-health --fix - Auto-fix with sudo (with consent prompt)
• eos debug repo-health --json - Machine-readable output for CI

Implementation

• Orchestration in cmd/debug/repo_health.go (<100 lines)
• Business logic already in pkg/repohealth/ownership.go
• Follow Assess/Intervene/Evaluate pattern

References

• pkg/repohealth/ownership.go - Core logic (80% test coverage)
• CLAUDE.md Architecture Enforcement rules