docs(archive): preserve PR 3156

docs/pr-discussions/PR-3156-chore-b-0506-file-stale-worktree-prune-cadence-row-1817z-tic.md

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+---
+pr_number: 3156
+title: "chore(b-0506): file stale-worktree prune cadence row + 1817Z tick shard"
+author: "AceHack"
+state: "MERGED"
+created_at: "2026-05-14T18:21:37Z"
+merged_at: "2026-05-14T18:23:27Z"
+closed_at: "2026-05-14T18:23:27Z"
+head_ref: "chore/b-0506-stale-worktree-prune-cadence-2026-05-14"
+base_ref: "main"
+archived_at: "2026-05-14T18:34:06Z"
+archive_tool: "tools/pr-preservation/archive-pr.ts"
+---
+
+# PR #3156: chore(b-0506): file stale-worktree prune cadence row + 1817Z tick shard
+
+## PR description
+
+## Summary
+
+Two-commit shipment for tick 2026-05-14T18:17Z:
+
+1. **B-0506 backlog row** (P3 friction-reducer): mechanize \`git worktree prune --expire=now\` via small TypeScript audit tool + per-tick or daily cadence wire-up
+2. **1817Z tick shard**: documents the 23-stale-worktree manual cleanup that triggered the mechanization row + side observation about an accidental stash-pop
+
+## Why now
+
+Prior tick (PR #3154, 1813Z shard) flagged the recurring "branch already used by worktree at <path>" lockout pattern when investigating PR #3153's Codex thread. The pattern was empirically caused by 23 stale \`/private/tmp/zeta-*\` worktree admin entries from yesterday's session crash — all with non-existent on-disk directories.
+
+\`git worktree prune --expire=now -v\` cleared all 23 in one shot at 18:17Z (worktree count 163 → 140). Manual command works; mechanization captured as P3 backlog row.
+
+## ID allocation discipline
+
+Per PR #3153's newly-merged otto-channels reference card ID-allocation discipline (both on-disk + in-flight check):
+
+\`\`\`
+$ find docs/backlog -name "B-*.md" -type f | grep -oE "B-[0-9]+" | sort -u -t- -k2 -n | tail -3
+B-0503
+B-0504
+B-0505
+
+$ gh pr list --state open --search "B-0506 OR B-0507 OR B-0508" --json number,title
+(empty)
+\`\`\`
+
+B-0506 safe — no on-disk collision, no in-flight contention.
+
+## Side observation: stash-pop hazard
+
+The shard captures a substrate-honest observation: a long-standing prior-session stash (\`stash@{0}: WIP on feat/b-0400-slice3-claim-coordinator\`) auto-popped during a \`git stash push <untracked-file>\` workflow and introduced conflict markers in unrelated files (\`tools/bus/claim.{ts,test.ts}\`). Both files were reset to \`origin/main\` state; stash content discarded (alternative SHA-256 lock-path variant; current encodeURIComponent approach is live and tested).
+
+## Test plan
+
+- [x] B-0506 row created in \`docs/backlog/P3/\` with full frontmatter
+- [x] On-disk + in-flight ID-allocation check passed
+- [x] 1817Z shard committed at canonical path
+- [x] Stash-pop hazard substrate-honestly preserved in shard
+
+🤖 Generated with [Claude Code](https://claude.com/claude-code)
+
+## Reviews
+
+### COMMENTED — @copilot-pull-request-reviewer (2026-05-14T18:25:16Z)
+
+## Pull request overview
+
+Adds a new factory-hygiene backlog row (B-0506) and a tick shard documenting the empirical stale-worktree cleanup that motivated it, to reduce recurring “branch already used by worktree” lockouts after session crashes.
+
+**Changes:**
+- Added tick shard for 2026-05-14T18:17Z documenting pruning 23 stale worktree admin entries and the motivating incident.
+- Added P3 backlog row B-0506 proposing mechanization (TS audit tool + cadence) for `git worktree prune --expire=now`.
+
+### Reviewed changes
+
+Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.
+
+| File | Description |
+| ---- | ----------- |
+| docs/hygiene-history/ticks/2026/05/14/1817Z.md | New tick shard capturing the stale-worktree cleanup and related operational observations. |
+| docs/backlog/P3/B-0506-stale-worktree-prune-cadence-mechanization-2026-05-14.md | New P3 backlog row proposing a mechanized stale-worktree prune cadence/tooling. |
+
+## Review threads
+
+### Thread 1: docs/backlog/P3/B-0506-stale-worktree-prune-cadence-mechanization-2026-05-14.md:14 (resolved)
+
+**@copilot-pull-request-reviewer** (2026-05-14T18:25:15Z):
+
+Frontmatter `type: feature` conflicts with the PR description calling B-0506 a “P3 friction-reducer”. If this row is meant to be tracked as a friction-reducer (as the text later implies), align either the PR description or the row’s `type` so tooling/triage doesn’t categorize it inconsistently.
+
+### Thread 2: docs/backlog/P3/B-0506-stale-worktree-prune-cadence-mechanization-2026-05-14.md:55 (resolved)
+
+**@copilot-pull-request-reviewer** (2026-05-14T18:25:15Z):
+
+The “Composes with” section references `claim-acquire-before-worktree-work.md` and `encoding-rules-without-mechanizing.md` without their `.claude/rules/` path. Since both files live under `.claude/rules/`, consider spelling the full path to make the reference unambiguous and easier to navigate/search.
+
+## General comments
+
+### @chatgpt-codex-connector (2026-05-14T18:21:44Z)
+
+You have reached your Codex usage limits for code reviews. You can see your limits in the [Codex usage dashboard](https://chatgpt.com/codex/cloud/settings/usage).