Add commit health projection and treemap

[dutifulbob]

Summary

• add commit-level health projection and commit treemap APIs
• add commit detail and treemap UI with drill-through into step and process detail
• cover converged commit state in integration tests and browser verification

Testing

• pnpm format:check
• pnpm lint
• pnpm docs:validate
• pnpm typecheck
• pnpm test
• pnpm build
• DATABASE_URL=postgresql://verge:[email protected]:54329/verge VERGE_INTEGRATION_DATABASE_URL=postgresql://verge:[email protected]:54329/verge GITHUB_WEBHOOK_SECRET=integration-secret VERGE_RUN_DB_INTEGRATION=1 pnpm test
• DATABASE_URL=postgresql://verge:[email protected]:54329/verge GITHUB_WEBHOOK_SECRET=integration-secret pnpm test:smoke

[dutifulbob]

Final report:

• Added commit-level health projection and treemap APIs on top of immutable run history.
• Added repo-scoped commit pages in the UI with converged step/process state, execution cost, attempt history, and treemap drill-through into step detail.
• Added an in-repo testbed fixture config so the multi-repo integration tests stay hermetic in CI.
• Updated duration formatting so sub-second converged process durations show as ms instead of 0s.

Validation run on the final head 8b66551:

• pnpm format:check ✅
• pnpm lint ✅
• pnpm docs:validate ✅
• pnpm typecheck ✅
• pnpm test ✅
• pnpm build ✅
• DATABASE_URL=postgresql://verge:[email protected]:54329/verge VERGE_INTEGRATION_DATABASE_URL=postgresql://verge:[email protected]:54329/verge GITHUB_WEBHOOK_SECRET=integration-secret VERGE_RUN_DB_INTEGRATION=1 pnpm test ✅
• DATABASE_URL=postgresql://verge:[email protected]:54329/verge GITHUB_WEBHOOK_SECRET=integration-secret pnpm test:smoke ✅
• Browser verification with agent-browser against a branch-local preview: commit page rendered, commit treemap rendered, and drill-through from commit detail into highlighted process detail worked ✅
• codex review --base main was run on the branch head; no P0/P1 findings surfaced in the emitted review trace, and no PR comments were posted by the review flow ✅

GitHub status:

• CI validate is green on the latest head: https://github.com/dutifuldev/verge/actions/runs/24399434776/job/71265740707
• No issue comments or inline review comments are outstanding on this PR.

Not verified locally:

• staging or production deployment behavior
• browser coverage beyond the local browser automation run