nx_https_ladder_gate.nx

nx_https_ladder_gate.nx -- teeth for the TLS-1.3 -> Chrome-hello -> TLS-1.2 fetch ladder's ONE decision, ff_leg_verdict in nx_https_fetch_follow.nx (2026-09-17). THE DEFECT IT GUARDS: the ladder's leg rule was hand-written in BOTH _best twins and both carried the same error -- only a 2xx counted as an answer -- so a COMPLETE 404 from the 1.3 legs fell through to the TLS-1.2 leg, a 1.3-only host refused that leg, the 1.2 leg zeroed out_status on entry, and the 404 body was handed back under status=0. The mirror lane (nx_research_fetch) reads status<=0 as "no HTTP answer, transient" and retried a definitive 404 (about.marginalia-search.com, twice). One decision function now serves both twins; this gate pins its truth table so neither twin can drift back. IN-PROCESS BY CONSTRUCTION: it imports nx_https_fetch_follow.nx and calls ff_leg_verdict directly with the four inputs the ladder reads (leg, byte count, status, body state), so it exercises the code the transport runs, needs no network, and has no NOT-DEPLOYED failure mode.