nx_recombine_novelty_gate.nx

nx_recombine_novelty_gate.nx -- THE R2 CLAIM GATE for the modeling lane (ladder head 1785858051). The ladder's top rung says: RECOMBINABLE = novel outputs sampled from the space, novelty PROVEN. nx_variant_mesh_gate already proves the 6 presets are valid + coarsely distinct; what it cannot say is that the generator RECOMBINES -- that a NEW point in the swap-slot space, one that is none of the presets, comes out valid and genuinely distinct, and that a duplicate would be CAUGHT. This gate proves exactly that: - a 7th, NOVEL recombinant tuple (human body + elf ears + tail, build 112 -- in the space, not in the preset list) is generated, closed, and distinct from all six presets - the distinctness floor is DATA-DERIVED (median pairwise distance / 8 = the near-duplicate band), never a magic constant: no pair may sit in the band - the NEGATIVE CONTROL regenerates a preset tuple and demands distance == 0: one measurement read from both sides -- generation is DETERMINISTIC (same tuple -> same descriptor) AND the duplicate detector provably fires below the floor (a tooth that cannot bite is not a tooth) Descriptor = shape + scale: a 4x4x4 occupancy histogram over the mesh's own bbox (per-mille, scale-free shape signature) + the bbox dimensions in grid units (so build-scale differences count). Integer-only throughout. license_tier: ORIGINAL No hw writes (Rule 26).