Add tests and docs for worktree reattach prune fix (#4394)

[rysweet]

Follow-up to #4394 (merged). Adds:

• 13 regression tests in tests/recipes/test_worktree_reattach_prune_4394.py
  • 5 static YAML analysis tests verifying prune placement after rm -rf
  • 8 live git tests confirming the bug/fix behavior
• Retcon doc docs/recipes/step-04-worktree-reattach-prune.md — problem statement, solution, 3-state diagram, reproduction steps
• README update — cross-reference in worktrees/README.md

All pre-commit hooks pass (ruff, pyright, prettier, secrets).

[github-actions]

Repo Guardian - Passed

All changed files in this PR are durable repository artifacts. No ephemeral content detected.

File	Assessment
docs/recipes/step-04-worktree-reattach-prune.md	✅ Durable recipe documentation for step-04-setup-worktree behavior
tests/recipes/test_worktree_reattach_prune_4394.py	✅ Regression test suite (issue number in filename is standard practice)
worktrees/README.md	✅ Durable documentation update

Generated by Repo Guardian for issue #4403 · ◷

[github-actions]

PR Triage Report

PR #4403 — Add tests and docs for worktree reattach prune fix (#4394)

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Classification

Field	Value
Type	Tests + Documentation (follow-up to merged #4394)
Risk	🟢 Low
Author	rysweet (repo owner)
Has Tests	Yes (13 regression tests)
Recommendation	Needs review before merge

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Files Changed

File	Status	Lines
docs/recipes/step-04-worktree-reattach-prune.md	Added	+138
tests/recipes/test_worktree_reattach_prune_4394.py	Added	+342
worktrees/README.md	Modified	+9

No production code changes. All changes are tests and documentation.

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CI Status

• ✅ 28 of 30 checks pass (Validate Code, GitGuardian, Root Hygiene, Docs validation, etc.)
• ❌ Check skill/agent drift — likely a false positive; no skill/agent files were added or modified
• ❌ Atlas PR Impact Check — likely a false positive; atlas staleness check triggered by new test file referencing the recipe, but atlas itself was not changed

Recommend verifying these two failures are pre-existing or unrelated infrastructure noise before merging.

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Test Coverage

• 5 static YAML analysis tests (verifying prune-after-rm-rf pattern in both State 2 and State 3)
• 8 live git tests (confirming bug/fix behavior with real git repos)
• Edge cases covered: no stale refs, healthy worktrees unaffected, double rm-rf, full YAML sequence simulation

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Suggested Labels

triage:low-risk · triage:has-tests · triage:needs-review · triage:complete

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Other Open PRs — Staleness Notice

The following PRs have been open for 16–18 days and are still awaiting review:

PR	Title	Age	Risk
#4216	feat: safe Anthropic disablement via ANTHROPIC_DISABLED flag	16d	Medium
#4199	fix(recipe-runner): auto-update rust runner binary on version mismatch	16d	Low
#4198	fix(knowledge_builder): guard --dangerously-skip-permissions against copilot binary	16d	Low
#4186	docs(multitask): add TIMEOUT_LIFECYCLE.md and update reference docs	16d	Low
#4112	docs: clarify required vs optional API keys in .env setup	18d	Low (external contributor)

PR #4396 (automated docs draft) expires today (April 19, 2026) and is labeled triage:auto-merge-candidate.

Generated by PR Triage Agent · ◷