nx_gzip_kat.nx

nx_gzip_kat.nx -- THE SOVEREIGN DEFLATE ROUND-TRIP KAT: the rostered tooth for /compare/performance PF3 (dynamic Huffman) and the lazy-matching rung, 2026-09-01. Until today the proof that gz_compress emits streams every inflater accepts lived in ONE session record (nx_gunzip by hand, zlib-strict on a laptop, GNU gzip on another machine). A proof nobody re-runs is a claim. This gate re-runs it on every roster beat against the SHIPPED artifacts -- the wasm module every world page carries and a served world page -- plus an adversarial synthetic set, through the estate's own inflater with its CRC32 and ISIZE checks armed. WHY THE TEETH ARE SHAPED THIS WAY: - round-trip = inflate returns EXACTLY n bytes AND every byte matches. A stub that copies input through fails the gzip-magic tooth; a stub that emits nothing fails round-trip; a stream one Kraft unit over-subscribed (the 2026-08-29 defect) fails inflate. - the MODULE must come back BTYPE=10 (dynamic) and under GK_MODULE_PERMIL_BAR. The bar is DERIVED from the board's own measurements on this module class: lazy+fixed measured 499 permil, zlib -9 429, lazy+dynamic 430. 460 sits between the encoder this rung replaced and the encoder it shipped, with 39 permil of margin to each -- so the fixed-Huffman encoder CANNOT pass this tooth and the shipped one passes it with room for input drift. Not a taste. - a TINY input must come back BTYPE=01 (fixed): the block choice is an arithmetic comparison per input, never a mode flag, and this is the input where fixed wins. - neg-control-corrupt-stream: one flipped byte in the compressed body must be REFUSED or must not reproduce the input. A round-trip oracle that cannot fail is decoration. - adversarial-kraft-limiter: gz_dh_lens over 40 exponentially skewed symbols (raw depth 39) must return a COMPLETE 15-bit code (Kraft sum exactly 2^15) with no length over 15 and no used symbol at 0. This is the arithmetic that came out one unit over on 2026-08-29. PRECONDITIONS are declared with gv_need (SKIP, never RED): the module and the page are estate artifacts that may be absent on a foreign tree. license_tier: ORIGINAL No hw writes (Rule 26). expect_exit: 0