nx_npc_atlas_gate.nx

nx_npc_atlas_gate.nx -- THE CLAY-FIX GATE (cw_npc_atlas, charsim+graphics watch contract). Subject: the SHIPPED world surface. Proves, on the LIVE docroot artifacts (never fixtures standing in for them): (1) the NPC asset carries TEXC (UVs) and TEXM (baked PBR maps) -- the DATA is real; (2) the TEXM albedo is a real, non-constant PNG -- a solid-color stub cannot pass; (3) the TEXC UVs are non-degenerate -- a constant-UV bake cannot pass; (4) every builtin world page carries the sampling path (aUV attribute, uAtl sampler, npc_atlas runtime marker) -- the WIRING is real; (5) bite: a page with the marker stripped is DETECTED (the detector fires on bad); (6) bite: the banked PRE-TEXM asset is DETECTED (a genuine pre-fix artifact, not a synthetic). DECLARED IMPRECISION (do not trust this gate as more than it is): pixel-level proof that the GPU actually sampled the texture is browser territory -- this gate proves data-real + wiring-real + refusal-real. The ship lane's cw_npc_atlas stage enforces the same contract IN THE PATH, so a clay ship cannot reach the docroot even between gate runs. Recipe-world pages are enforced by that ship stage; this gate re-checks the three BUILTIN pages independently (scope printed, not implied).