The one-shot Flutter CLI commands passed their command signal to the
inspection but not to finishAnalysisCommand, whose post-close cancellation
guard only runs when a signal is supplied. When the provider's first
snapshot-root removal failed, close() retried it after the inspection had
returned; SIGINT during that retry set exit status 130 while the command
still printed ordinary successful Evidence.
Pass the command signal to the finisher so an abort observed after the
awaited cleanup retry yields typed cancellation that retains the completed
Evidence as partial_observation. A failed retry still reports
cleanup_incomplete ahead of the later signal.
Fixes#4640
Co-authored-by: Claude Opus 5.5 <[email protected]>
