tests/mutations/r2_flow.toml: 18 falsifiers, each proved RED under its
change by scripts/mutation_check.py (18/18). Its first run found three
vacuous proofs, now resolved:
- landed_at's per-entry skip: the symlink-loop fixture stopped raising
once the clock moved to lstat. New fixture: a folder that lists but
cannot be searched.
- the Desk's bench URL guard: the test covered bookmarks only. A
hand-edited registry bench now rides with it.
- flagged_targets' `error is None`: defence in depth (hydration already
strips a damaged mark's target), so no single-guard row; named in the
table header instead.
The rail's flagged filter and the orphan-flag list read flagged_targets
rather than restating it; no reachable behaviour changes.
vh
39a3cb2262