Four cases on real data: each leg's real verdict, plus the android trace
cut before it reached the transaction screen, which is what proves the
route gate reads a real hierarchy dump.
Also corrects the hand-written fixtures. They set is_error to false on a
plain violation; internal/trace/writer.go tags that field omitempty, so a
real trace omits it entirely. Harmless to the classifier, but a fixture
that does not look like reality is the thing that hides drift.
21 cases through a stubbed sanderling: every exit path, the drift check,
a missing trace, a zero-byte trace, an empty glob and a truncated line.
Asserts the flags that reached the binary, not just the exit code.
Invoked as bash -eo pipefail -c, which is what a run: block does. Running
folio-run.sh itself under -e would kill it at the first non-zero
sanderling test, which is the exit code it exists to read.
pj