The blueprint-sweep terminal rendered BindError via {:?}, leaking
KindMismatch { .. } and MissingKnob(..) Rust Debug structs where the
sibling diagnostic on the same verb ships prose. Both now render in
that register — the axis name, the expected-vs-supplied kinds resp.
the unbound knob, and the --list-axes pointer; exit stays 2.
Scoped out (same defect family, different verb path): the walkforward
path's UnknownKnob wrapper still prints its Debug-ish frame around an
already-prose payload and is pinned verbatim by two existing tests;
filed as a follow-up rather than widened into this slice.
closes#247
claude
414448bd3f