docs(upstream): re-audit the pstack record past cursor/plugins 99743e9c15 and re-pin it #8542

Refs: #7588

Agent Brief

Type: Task
Summary: Re-audit docs/upstream/cursor-pstack.md against current pstack, covering the 0.15.25 release and cursor/plugins#633 and #634, re-map the principle rows #633 restated, and move the pin so the drift check comes back clean.

Current behavior:

• The record is pinned at cursor/plugins@118e73b0e196e4d49d5aade7ce6dd8985a621f68 under pstack/ (pstack 0.15.21) (docs/upstream/cursor-pstack.md:10).
• bash scripts/check-upstream-drift.sh --page docs/upstream/cursor-pstack.md reports drift (run 2026-10-20): changed paths behind the rows at cursor-pstack.md:95, 96, 98, 99, 100, 105, 125, 268 (trace-forensics, session-pickup, correct, ketchup, poteto-help, why, arena, show-me-your-work) and five new units: pstack/docs/harness/claude-code.md, skills/create-formal-verification-skill, skills/in-your-own-words, skills/maintain-formal-verification-skill, skills/sharpen.
• pstack: restate four overspecified principles as reasoning, not rules cursor/plugins#633 ("restate four overspecified principles as reasoning, not rules", merged 2026-10-15) and refactor(source-control): one shared babysit authorship/finding/approval classifier + golden fixtures (#534) #634 ("cut marginal sections from four skills", merge commit 99743e9c151c8537cbbf1f98bb38f34ef3368453) changed principle and skill text the record's principle rows map (cursor-pstack.md:57, 79-86).
• Upstream moved past 99743e9c15: on 2026-10-20 its HEAD was 88d47514b82e7c44f00f2b2a72ff6dd12158038c, 53 commits later, 26 of them touching pstack/. A pin at 99743e9c15 would leave the drift check reporting those 26 paths.
• rg -c '99743e9c15' docs/upstream/cursor-pstack.md prints nothing on main.

Desired behavior:

• The **Last audited upstream state:** line pins the upstream HEAD commit the lane reads at the start of its run (40-hex sha, under pstack/, with the pstack version from pstack/plugin.json at that commit). That commit contains 99743e9c15.
• The paragraph under the pin line says what changed between 118e73b0e1 and the new pin, and names 99743e9c15 as the commit where work-items:triage: umbrella-fold routing misses the umbrella-side membership comment (item-side only, 3x this session) #633 and refactor(source-control): one shared babysit authorship/finding/approval classifier + golden fixtures (#534) #634 landed, so the re-map is traceable.
• Every row the drift check names is re-checked at the new pin and gets a "Re-checked at <short sha>" stamp in the record's existing style. A row whose verdict changes says why.
• The principle rows work-items:triage: umbrella-fold routing misses the umbrella-side membership comment (item-side only, 3x this session) #633 restated are re-read and their mapping updated where the restated reasoning changes what our skill takes; a row refactor(source-control): one shared babysit authorship/finding/approval classifier + golden fixtures (#534) #634 cut sections from is checked for a mapping that pointed at the cut text.
• Each new unit gets a row or a "Not adopted (decided, with reasons)" entry. sharpen and the two formal-verification skills are not adopted now: sharpen is deferred under discipline: paved-path file and principle placement #7589, and a formal-methods skill is parked (docs/upstream/tlaplus-agentskills.md); the entries say so and name what would reopen them.
• The old ladder rung ids in this record (canonical-helper, llm-only) are updated to the ladder 2.0.0 ids if the ladder-v2 slice of enforcement-ladder: v2.0.0 ladder and one guardrail criterion #7572 has merged; otherwise left as they are.
• Only docs/upstream/cursor-pstack.md changes.

Key interfaces:

• docs/upstream/cursor-pstack.md (pin line, Attribution table, "Not adopted" section, ## Map).
• scripts/check-upstream-drift.sh and the page forms in docs/conventions/upstream-drift/README.md, "Pinned git upstreams".
• Upstream reads with gh api repos/cursor/plugins/... at the pinned sha.

Acceptance criteria:

• rg -c '99743e9c15' docs/upstream/cursor-pstack.md is at least 1.
• The PR's CI runs bash scripts/check-upstream-drift.sh --page docs/upstream/cursor-pstack.md and it passes.
• The PR's CI runs bash scripts/check-upstream-drift.sh --links --page docs/upstream/cursor-pstack.md and it passes.
• rg -c 'sharpen|in-your-own-words|create-formal-verification-skill|maintain-formal-verification-skill|docs/harness/claude-code' docs/upstream/cursor-pstack.md is at least 5.
• git diff --name-only origin/main lists only docs/upstream/cursor-pstack.md, so scripts/check-changelog-fragments.sh --check-required origin/main passes with no fragment.
• CI's lint-repo job (markdown lint, purged em-dash gate) passes.

Out of scope:

• Placing re-mapped principle parts in skills (discipline: paved-path file and principle placement #7589's principle-placement slice).
• The local principles map in the planning workspace; it is not tracked.
• Rewording the nine passages docs: reword nine pre-existing passages that track upstream pstack and mattpocock text #7052 tracks.
• The listing budget (sibling slice listing-budget, waits on skill-quality: skill authoring, quality and catalog #7582's pilot).
• Any plugin file.

Origin:

• One pstack recheck PR covering 0.15.25 plus work-items:triage: umbrella-fold routing misses the umbrella-side membership comment (item-side only, 3x this session) #633 and refactor(source-control): one shared babysit authorship/finding/approval classifier + golden fixtures (#534) #634: ours, D0, Q557, D116.
• Pin at the upstream HEAD read at run time instead of exactly 99743e9c15: ours, this triage. Upstream moved 53 commits past 99743e9c15 by 2026-10-20, so only a pin at HEAD lets the drift check exit 0; HEAD contains 99743e9c15, so the decision's coverage holds. The owner may object when filing.

Do not run with: the ratchet-move slice of #7584 (it edits cursor-pstack.md:98 to rename /review:ratchet).

Slice of #7588, drafted by the Issue Triage session from the thread's recorded decisions.