Milestone acceptance corpus for 'Measurement as a first-class citizen',
authored as a downstream consumer (public interface only): a gated
rate/mux/counter over the four new cells, a SessionFrankfurt anchor study,
and the origin first-candle-momentum study on real GER40 data — each a
hand-authored blueprint plus one recorded run, zero throwaway Rust. The
three capabilities compose end-to-end and record via declared taps.
Findings routed separately: two aura-run panics-where-refusal-expected
(bad tap wire; non-bias output) to debug; a tap-authoring friction and two
doc gaps to follow-ups.
