Teach the shared-refs family rule at recipe level (worktree isolates tree and HEAD only)

[os-zhuang]

Fixes#10743

What

Teaches the family rule at recipe level, per the grading scope: git worktree isolates the working tree and HEAD, and nothing else under .git/ — refs (including refs/remotes/*), the stash stack, config, hooks are common to every worktree. A recipe is worktree-safe only if it never names shared state.

.claude/agents/os-dev.md (395 before, 399 after, ceiling 399):

• Rule 1 (worktree-first) now records the base at branch time: BASE=$(git rev-parse HEAD) before any work.
• The stash clause is rewritten into the family rule, stated once in the file's voice, with the family signature (operation looks local, reports success, only symptom is other agents' files in git status) stated once for both instances. It adds the shared-pointer hazard — git reset --soft origin/main stages other agents' merged files, landed after your branch point, as yours (measured shape: four agents' merged files staged by one soft reset, caught pre-commit) — and the discipline: "where I started" reset/diff/log/rebase anchor the recorded "$BASE".
• Net +6 paid down to +4 (exact headroom) by deleting two genuine in-file duplicates: resource rule 6's lock-queue-is-the-only-legal-wait sentence (fully stated by rule 7 and clean-finish item 4) and rule 6's SIGTERM-mid-ablation incident sentence (fully stated in the ablation clause together with its trap remedy).

.claude/skills/pm-dispatch/references/platform-readings.md (134 before, 134 after, ceiling 134 — zero headroom):

• New single-line fact row in the reading-traps section: shared refs/remotes/origin/main, the soft-reset failure shape, and the recorded-base-sha discipline.
• Paid 1 line by deduplicating inside the merge-queue timeline bullet: the queue-branch ls-remote spelling (kept verbatim in the zero-cost-equivalents row, now pointed to) and the positive-hit-sufficient reading (also carried by the enable-verify sequence). The queue-saturation boundary fact is retained; no fact or safe procedure deleted.

Conditional surfaces — no carrier spelling found

Grepped AGENTS.md, CLAUDE.md, pm-dispatch SKILL.md and the dispatch runbook for recipes anchoring origin/main as an implicit "where I started": every hit is either a deliberate read of current main (premise verification, git merge origin/main in merge-queue context, same-day churn scans) or an already-taught hazard description (the checkout-from-ref clauses). Their stash-alternative recipes anchor HEAD~1 / implicit HEAD, which is worktree-safe. Per the adjudicated scope, no new sections were added to those files.

Verification

All 8 derived gate families green at head 194dcb7e9 (union re-run after the final commit; node scripts/pm/dispatch-gates.mjs with no hand-fed paths derived the set):

• check:pm-skill-ratchet — "✓ check-skill-line-ratchet: .claude/agents/os-dev.md is 399 lines (ceiling 399; headroom 0)." and "✓ check-skill-line-ratchet: .claude/skills/pm-dispatch/references/platform-readings.md is 134 lines (ceiling 134; headroom 0)."
• check:pm-skill-id-lint — "✓ check-skill-id-lint: 17 file(s) clean (pattern /#[0-9]{3,}/g)."
• check:doc-authoring — "✓ doc authoring guard: 389 files clean — no bare metadata literals."
• check:nul-bytes — "check-nul-bytes: OK (scanned 6446 text file(s) ...)" plus the extra-gate control-byte self-scan on both touched files (no hits).
• check:agent-model-declared, check:pm-governed-merges, check:skill-frame-sync, check:doc-formula-expressions — all self-tests and scans green (verdict lines in the report comment).

Docs-only .claude/ change: no changeset; skip-changeset label applied via the additive POST with read-back after bots settle.

Governed surfaces — draft PR, human merge only.

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Generated by Claude Code

[os-zhuang]

PM 验收 — ACCEPT（终态）

复核：席位 session_01MsbKEG4LtERSLaDrbehM3e 全 diff 审毕（+17/−13 两文件）。裁定范围逐项落地：家族规则（worktree 只隔离工作树与 HEAD，.git/ 下 refs/stash/config/hooks 皆共享；家族同签名一处陈述覆盖 stash 与共享指针双实例）以配方层写入 os-dev.md——规则 1 增 BASE=$(git rev-parse HEAD) 记录点，「我从哪开始」的 reset/diff/log/rebase 一律锚 "$BASE"、⛔ 永不锚 origin/main。棘轮支付双双核实为真删非 re-wrap：os-dev.md 399/399（规则 6 两句确属重复——锁排队唯一合法等待由规则 7 + 干净收尾完整承载，SIGTERM 中途消融事例由消融条款连同 trap 补救完整承载）；platform-readings 134/134（队列分支拼写指向零成本等价物行原文、负向推断句压缩重述，零事实损失）。条件面四文件全部实测「无载体拼写」不扩面——AGENTS.md 961/961 未动，正确。讽刺守卫自证（本单自身以记录 base sha 锚定 diff）。

治理面终态：draft 保持，仅维护者合并；已指派。⚠️ 落地提示：本 PR 入队时同样会撞 Console Pin Gate 的确定性红（与 #11126/#11129 同因）——建议与那两单一起，等 objectui#5710 → #10856 pin bump 落地后一次性重投/入队三单。合并后剥 #10743 状态标。

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Generated by Claude Code