[Phase 5] Pilot on .github: enroll the driver stub, arm epic #505, confirm cross-repo auto-release

[github-actions]

Story

As a maintainer,
I want enroll the initiative-driver stub in petry-projects/.github, arm its epic #505 with initiative:auto, and confirm the central driver auto-releases the epic's ready DAG cross-repo with no manual dev-lead labels,
so that we validate the fleet release path end-to-end on a real epic before any broader rollout.

Acceptance Criteria

1. petry-projects/.github has the initiative-driver stub enrolled (the Story 2 template copied to its .github/workflows/initiative-driver.yml) and GH_PAT_WORKFLOWS available there.
2. The petry-projects/.github epic [Phase 1] Tag protection + document scoped mutable-ref exception to SHA-pin standard #505 is armed with initiative:auto; the central driver releases its first ready wave (and successors as they close) by labelling them dev-lead in .github — with no manual labelling.
3. The cross-repo release is observed working: a driver run logs the target repo and dev-lead picks up in .github; the canary (Story 3) is green and Fleet Monitor (Story 4) shows the .github driver stub enrolled/aligned.
4. Pilot findings (release latency vs the safety-net cron, PAT scoping, any MAX_IN_FLIGHT observations) are recorded back on the epic for the go/no-go on wider rollout.

Tasks / Subtasks

• Copy the Story 2 stub template into petry-projects/.github/.github/workflows/initiative-driver.yml and confirm GH_PAT_WORKFLOWS is present there. (AC: test issue from agent #1)
• Verify the .github epic [Phase 1] Tag protection + document scoped mutable-ref exception to SHA-pin standard #505's sub-issues carry native blocked_by edges (the driver gate depends on them), then add initiative:auto to the epic. (AC: Go-live improvements for PR review agent #2)
• Observe the cross-repo release (driver run logs + dev-lead pickups in .github); confirm the canary + Fleet Monitor signals are healthy. (AC: Add @claude delegation, auto-merge, and rebase handling #3)
• Record latency/PAT/cap findings as a comment on the epic. (AC: Optimize review: small-PR and incremental fast paths #4)

Dev Notes

• This is a cross-repo + human-judgment activity, so hands_off:true: arming initiative:auto is a human decision by hard rule, and enrolling a stub in petry-projects/.github is a cross-repo change dev-lead cannot make from a .github-private issue.
• IMPORTANT: '.github epic [Phase 1] Tag protection + document scoped mutable-ref exception to SHA-pin standard #505' is the epic in petry-projects/.github — NOT .github-private issue [Phase 1] Tag protection + document scoped mutable-ref exception to SHA-pin standard #505 (which is the closed 'Tag protection' story; issue numbers collide across repos). Do not treat them as the same issue.
• The driver gate keys on native blocked_by relationships and the initiative:auto label on the epic; confirm both exist in .github before arming, or the sweep will no-op / release everything at once.
• Depends on the stub (Story 2), and on the canary + Fleet Monitor (Stories 3, 4) so any regression surfaces DURING the pilot, and on the docs (Story 5) so the operator follows a documented enrollment runbook.

Project Structure Notes

Cross-repo + operational: enrollment and arming happen in petry-projects/.github. No .github-private code change in this story.

References

• docs/initiatives/agentic-release-strategy-orchestration.md#operating-the-driver-runbook
• .github/workflows/initiative-driver.yml
• scripts/initiative-driver.sh#drive_epic (gate / cap / blocked_by logic)

Likely target surface

• petry-projects/.github: .github/workflows/initiative-driver.yml
• petry-projects/.github: epic #505

Story prepared by the BMAD Scrum Master (Bob) for epic #882. Status: ready-for-dev.