e5f4155e

By: Kaapo Seppänen <seppanenkaapo@gmail.com>

unify scalar CFF sector generation across medium modes

Keep polynomial numerator decomposition and interpolation independent of
the medium. Route remainders, contacts, terminal sectors, and zero-edge
sectors through the shared scalar builder, which owns medium-specific
weights, contour choices, and normalization.

Remove duplicated dispatch and consolidate variant remapping so thermal
weights and sign provenance survive lifting together.

Validated with 141 crate tests, the inverse-propagator cancellation
inspect test, cargo check, formatting, and strict Clippy.

Timeline