nx_vq.nx

nx_vq.nx -- VECTOR QUANTIZATION, the first rung of the sovereign neural-audio moonshot. Instead of scalar-quantising each LPC reflection coefficient (D coeffs x 8 bits), VQ maps the WHOLE coefficient vector to the nearest entry in a learned codebook and transmits one small index (log2(K) bits). This is the exact classical precursor to the residual vector quant(RVQ) codebooks inside SoundStream / Lyra-v2 -- the lever that takes our DRED redundancy overhead from ~44 kb/s (scalar i8) toward the 12-32 kb/s neural target. The codebook QUALITY (coverage of the space) is the training problem whose ceiling is the neural net; the VQ MECHANISM here is exact + integer. license_tier: ORIGINAL