nx_bom_hb.nx

nx_bom.nx -- LIB: component library + supply-chain BILL OF MATERIALS, as a digital twin of real procurement. A parts library carries REAL data per part (mfr part number, unit price in CENTS, available stock). A design maps each component instance to a library part; the BOM aggregates by part -> quantity + extended cost, sums an EXACT integer total (no float rounding -> what you'd really pay), and flags supply-chain SHORTFALLS (required qty > stock = can't source). Composes the schematic's component list (schematic -> ... -> BOM). Data-driven: adding a part = a library row. never-brick #26: pure arithmetic, bounded, deterministic. license_tier: ORIGINAL