Add loop worktree story

[k-anushka14]

Summary

Adds a week-two story on using loop-worktree (paired with loop-context) with the PR Babysitter pattern.

Changes

• New pattern or starter (followed templates/pattern-template.md + updated registry.yaml)
• Doc / example improvement
• Tool change (loop-audit)
• Story (includes real failure or surprise + lesson)

Checklist (from CONTRIBUTING)

• All required sections present for patterns
• Links work from README, patterns/README, starters/README, docs/index
• No secrets, tokens, internal company URLs
• STATE.md* examples use .example suffix
• Safety-related content references docs/safety.md
• Ran node tools/loop-audit/dist/cli.js . (or on the starter) and addressed findings

Testing / Dogfood

• loop-audit passes on affected starters or this repo
• Manual review of generated state / skill output

Screenshots / Examples (if UI or command output)

Commands actually run to produce the story:

• loop-worktree create --run-id pr-42-fix-1 --pattern pr-babysitter
• loop-worktree mark --run-id pr-42-fix-1 --status rejected
• loop-worktree cleanup --status rejected --older-than 24h
• loop-context --check --ledger run.json --stagnation 3 --json

Closes #229

[github-actions]

Thanks @k-anushka14 for contributing a production story — visible, reviewable PRs like this grow the reference for everyone.

What happens next

• Maintainer aims for same-day review on story, adopter, and scoped docs/example PRs (CONTRIBUTING.md).
• good first issue PRs: comment on the linked issue so we can assign and close on merge.

More ways to help

• Contributor quickstart + open issues
• Good first issue backlog

— loop-engineering maintainers