Unit: walker all-or-nothing bounds (exceeded -> nothing removed + distinct
result; exact bound -> deletes), protected-prefix skipping, config wire
round-trip for force_delete/delete_excluded/prune_empty_dirs/max_delete, CLI
parse/validation for the new flags. Integration (TestDeletePolicy): default
delete-excluded protection and --delete-excluded opt-out (single-thread, -m,
early --delete-before, excluded-dir subtrees), --max-delete all-or-nothing over
and at the limit, --force file-over-nonempty-dir replacement, --prune-empty-dirs
(--dirs mode + recursion-mode parity), and --ignore-errors keeping deletion
active across a genuine scan I/O error (run as an unprivileged user).