contribution-gate-playbooklisted

# Contribution Gate Playbook The observed, repo-verified pipeline that took #85–#89 → PR #90 (`a148180`), #91 → PR #93 (`92077a7`), and #94–#96 → PR #97 (`79ca49c`) on 2026-07-29/30. Canonical gate doctrine is `skills/cross-model-review/SKILL.md` — this file only pins how THIS repo runs it. On any disagreement, the canon skill wins. ## Step 0 — pin the campaign set Trigger: the owner's ask arrives. - The set = the PRs open at instruction time (`gh pr list --state open`). Record the numbers before touching anything. - A PR that opens mid-campaign is NOT swept in. Precedent: #91 opened 2026-07-29T22:18Z, before #90 merged (23:34Z); it was excluded from #90, flagged to the owner, and handled as its own campaign (#93). - The owner's ask authorizes THIS set; a later set needs a fresh ask (operational-rigor §2, per-invocation grant). ## Step 1 — verify each PR's verifiable claims - Every repo-facing claim in a PR's text (a commit id, a section number, a "main already says X") is checked against the repo BEFORE the gate. Precedent: #85's `8f8413f` incident claim was verified in-repo, and the check is recorded in #85's evaluation comment. - A claim that fails verification is a finding to surface and adjudicate, not something to silently fix or silently accept. ## Step 2 — build the combined branch - One integration branch from current main, named by joining the PR numbers — `combined-85-86-87-88-89`, `combined-94-95-96` (multi-PR) or `integrate-91` (single