Static assertion that every Tier-A primitive in PRIMITIVE_REGISTRY
has a slot in the calibration grid (hard gate or conditional set).
Excludes Tier B (8 cross-session primitives) and Tier C (toolchain.*)
by explicit allow-list and prefix filter.
Three checks:
* every Tier-A primitive is covered (forward direction)
* no extractor set drifts from the registry (reverse, catches typos)
* Tier-A count == 37 (design doc invariant)
CI now fails before a registry addition ships without a feature
function.