* fix(#2838): SUMMARY rescue handles gitignored .planning explicitly
The pre-fix rescue used `git ls-files --modified --others --exclude-standard`
to detect uncommitted SUMMARY.md before worktree removal. When projects
gitignore .planning/, --exclude-standard filters out the very files the
rescue is meant to save, the rescue branch is skipped, and `git worktree
remove --force` permanently deletes the SUMMARY.
Replace both rescue blocks (quick.md, execute-phase.md) with a
filesystem-level find + cp rescue that bypasses gitignore entirely and
avoids the worktree↔main commit/merge cascade. cmp -s makes it idempotent.
Adds tests/bug-2838-summary-rescue-gitignored-planning.test.cjs which
extracts each rescue block, runs it against a real temp repo with a
gitignored .planning/, and asserts the SUMMARY survives worktree removal.
* test(#2838): assert rescue block exits 0 in idempotency test
CodeRabbit (Minor): the idempotency test pre-creates the destination
SUMMARY.md, so even a syntax/runtime error in the rescue block would
silently false-pass. Add an explicit r.status === 0 assertion.
4815b3c972