feat: CI/CD lifecycle hooks for external pipeline integration

[nigel-dev]

Source

Audit report — Section 9: Phase 3 Roadmap

Description

MC operates entirely locally. There is no integration with CI/CD pipelines — when MC creates a PR, it has no way to monitor CI status, trigger deployments, or gate merges on external pipeline results.

Proposed Solution

1. PR status monitoring: After mc_pr creates a PR, optionally poll GitHub checks API for CI status
2. CI-aware merge gating: Don't merge (or warn) if CI checks are failing on a job's branch
3. Post-merge hooks: Run configurable commands after a successful merge (e.g., deploy, notify)
4. Webhook support: Accept webhooks from CI systems to update job/plan status
5. Pipeline templates: Define pre/post hooks per project in MC config

Use Cases

• Wait for CI to pass before merging a plan's integration branch
• Trigger staging deployment after all plan jobs merge
• Notify Slack/Discord on plan completion
• Block PR creation if branch CI is failing

Priority

P3 — long-term integration feature. Current workaround is manual CI checking after PR creation.