Mirror family-keyed quorum into pull-request-workflow.md §6.1.1

Context

Sub of Epic #11796 (active-peer quorum rule). Covers AC2 — PR-merge-gate mirror. Depends on the merged shape of #11799 (the source-of-truth ideation-sandbox-workflow.md §6 amendment).

Scope

Single-file amendment: .agents/skills/pull-request/references/pull-request-workflow.md §6.1.1 (Consensus-Gate). The companion Axis 2 of the consensus mandate (PR-merge-gate, per ideation-sandbox-workflow.md §6.8).

Prescription

Amend pull-request-workflow.md §6.1.1:

1. Reviewer Signal Ledger check. Replace any "3 peer rows" verification language with family-keyed verification: "PR reviewers MUST verify the Signal Ledger (per ideation-sandbox-workflow.md §6.6) has (a) ≥ 2 active families carrying any signal, AND (b) ≥ 1 non-author family [GRADUATION_APPROVED]. Reviewers consult AgentIdentity.participationStatus (per ai/graph/identityRoots.mjs) to confirm which families are active."
2. AUTHOR_SIGNAL recognition. Add explicit language: "[AUTHOR_SIGNAL] from the PR-source Discussion's author is NOT sufficient as cross-family endorsement at the PR-merge gate; ≥ 1 non-author family [GRADUATION_APPROVED] is required regardless of how many family slots the author covers."
3. Tier-2 PR-merge-gate. For PRs from Tier-2 Discussions (core-value / §critical_gates / consensus-gate mutations), reviewers MUST additionally verify the PR body's ## Unresolved Liveness section names any benched family + a revalidationTrigger AC per Epic #11796 AC6.
4. §6.1.1 anchor citation update. Replace any prior "3×" cite with the membership-derived rule + cite both ideation-sandbox-workflow.md §6.2 and Epic #11796.
5. closeoutGates template (if present in this file). Update to reflect family-keyed verification.

Acceptance Criteria

• AC1 — §6.1.1 "verify Signal Ledger" language is family-keyed and references AgentIdentity.participationStatus.
• AC2 — AUTHOR_SIGNAL explicitly named as insufficient for cross-family endorsement at merge.
• AC3 — Tier-2 PR-merge-gate adds ## Unresolved Liveness verification step.
• AC4 — All "3×" cites in §6.1.1 (and its references) replaced with the membership-derived rule.
• AC5 — Cross-references to ideation-sandbox-workflow.md §6.2 / §6.6 / Epic #11796 are present and accurate.

Out of Scope

• The actual ideation-sandbox-workflow.md §6 amendment (sibling sub #11799).
• AGENTS.md mirror (sibling sub, separate file + byte budget).
• identityRoots.mjs structured field (sibling sub).

Sequencing

Wait for #11799 to merge before opening the PR for this sub — verbatim semantic borrowings from §6.2 must reference the final §6.2 prose.

Related

• Parent Epic: #11796.
• Depends on: #11799 (source-of-truth amendment).
• Source Discussion: #11793.