Why:
An interrupted multi-component transition must retain original staged, ignored and external-worktree data after some independent copies have completed.
Evidence:
SELF scratch fixture interrupts a real nested copy after App is saved and Logging is partially copied; originals and external Git metadata remain identical, recorded partial data persists and retry refuses to discard it.
Impact:
Add failure-path coverage and clarify reachability checks before component branch cleanup; no transition implementation change.
Refs:
Dependency-workspace R9/R15 and independent reliability coverage followup.
weichen
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