nx_nv1_lpc_gate.nx

nx_nv1_lpc_gate.nx -- ENGINEER gate for the NV1 LPC rung (nx_nv1_lpc.nx). Evidence-driven, re-runnable, no network. Proves: 1. BIT-EXACT round-trip (decode(encode(x)) == x byte-for-byte) on every signal class: silence, DC, ramp, triangle, full-range LCG noise, speech-ish (triangle + dither), alternating extremes, tiny blocks. 2. FLAC-CLASS compression measured in permil of raw bytes (asserted ceilings per class; printed so the ratio is ON the log). 3. The verbatim escape: noise NEVER expands past 6 + 2n. 4. Container integration: an 'L' chunk validates under nv1_validate and its samples are counted. 5. Every decoder rejection class fires its named negative. license_tier: ORIGINAL