nx_fbx2nxa_gate.nx

nx_fbx2nxa_gate.nx -- THE FBX IMPORTER GATE: the unit factor is MEASURED, ANNOUNCED, APPLIED, and REFUSED when forged -- proven on the promoted binary over the FULL donor population. Subject: ./nx_fbx2nxa.elf (the serving-root binary; e2e fork, never an in-process re-derive). All four real donors carry UnitScaleFactor = 1.0 (GlobalSettings dumped 2026-08-23), so the factor legs are proven by FIXTURE: a byte-patched copy of the smallest donor with the D-value set to 2.0 (heights must EXACTLY double, within the derived truncation bound below) and to 0.0 (must REFUSE by name). A multiply-by-identity implementation cannot pass the 2.0 tooth -- that is the anti-vacuity. Neutrality: at factor 1.0 every donor's output must be BYTE-IDENTICAL to the shipped knowledge/rigcorpus/*_geom.nxa, all four, no sampling. NOT roster-admitted: imports the 73.6 MB toon donor in-process (multi-second subject; the voxchunk precedent -- the roster beat kills at its declared bound). The absent-record leg (-1 -> announced assumed 1.0) is DECLARED UNTESTED-BY-FIXTURE: no real FBX lacks the record and synthesizing a whole valid record-free FBX would test the synthesizer, not the importer. Covered by code-read; named here so nobody mistakes silence for proof.