Multi-account upgrade path: formal review signals

[deanbot]

Context

The current spec (v0.1) is single-account only — GitHub blocks self-approval so formal APPROVED / CHANGES_REQUESTED review submissions are inaccessible. The comment-prefix protocol ([reviewer], [executor]) is the workaround.

With a second GitHub account for the reviewer agent, formal review signals become available, enabling branch protection rules and proper merge gating.

What "done" looks like

• spec/SPEC.md has a "Multi-account mode" section documenting delta in signal handling, merge threshold, and comment protocol
• pr-poll.mjs handles NEW_REVIEW_SUBMISSION with formal APPROVED state as MERGE_READY contributor (behind --multi-account flag or auto-detected)
• adapters/claude-code/skills/start-executor/SKILL.md updated with multi-account signal handling
• adapters/generic/executor.md updated same
• Minimum GitHub config documented: reviewer account as collaborator, branch protection requiring 1 approval
• Spec clearly describes both modes and what differs
• Scripts handle multi-account signals without breaking single-account behavior
• Adapter prompts note which mode they implement

Notes / Open questions

None yet.