nx_ark_snapshot.nx

nx_ark_snapshot.nx -- X-REP-005 (CALLOUT-002 REP-1): the ARK. Packs the data-driven survival set (knowledge/registry/ark_set.tsv) into ONE file with a CID manifest -- the dead-laptop seed's first organ. snap (default): read every set row -> entry CIDs -> manifest text. If the manifest is BYTE-IDENTICAL to the existing one, SKIP the pack write entirely (unchanged=1; the resource-conscious beat is a read pass). Else write pack.new + manifest.new and renameat both (atomic; the lane's temp-rename discipline). verify: walk the pack against the manifest -- entry count, path, size, recomputed CID must all match; any mismatch = named row + RED. An ark that cannot prove itself is hope, not backup. Pack format NXARK1: "NXARK1\n" then per entry "ENT <pathlen> <bytes> <cid>\n" + path bytes + raw content. Manifest rows are DETERMINISTIC (no epoch -- epoch lives in the ARKSNAP log row only) so unchanged detection is a byte compare. argv[1]=mode snap|verify argv[2]=set argv[3]=pack argv[4]=manifest Evidence: ARKSNAP / ARKVERIFY rows -> stdout + knowledge/status/ark.log. license_tier: ORIGINAL