nx_ppmi_lib.nx

nx_ppmi_lib.nx -- THE canonical PPMI model library (eats debt seq283). The loader + sparse-merge cosine over knowledge/index/semppmi_v1.bin had been hand-rolled twice: pb_* inside nx_recall_dense.nx (the recall lane's reranker) and sj_* inside nx_dr_semjudge.nx (the deep-research judge). Two copies of the same numeric code silently diverging would change similarity scores without any gate noticing -- exactly the drift class D001 was raised for. This is the ONE copy both should import. MIGRATION STATE (honest): nx_dr_semjudge migrates onto this lib now. nx_recall_dense is a LIVE organ owned by the recall lane and is NOT edited here -- it migrates on its owner's next touch (D001 migrate-on-touch), at which point seq283 fully closes. Model format (NXPPMI1): 32B header [magic, nv, nt] then vocab-hash[nv], row-index[nv+1], norm^2[nv], ctx-id[nt], value[nt]. Vocabulary is keyed by db_semhash -- resolving a word with any other hash silently yields -1 and zeroes every similarity. Every func <=6 params (NAS nx_cc >6-arg skew, seq239). No hardware writes (Rule 26). module: nishi-core.index.ppmi_lib depends: nx_qabench_engine.nx (db_semhash/db_bsearch_i64), nx_syscalls.nx genealogy_id: levy_goldberg_2014_ppmi