nx_damages_lib.nx

nx_damages_lib.nx -- PREJUDGMENT INTEREST / money damages over time. Integer-exact, composes nx_sol. A money judgment is rarely just the principal: statutes award prejudgment interest from the date of loss (accrual) to the date of judgment. Getting it right means an EXACT day count (not an approximation) and the correct convention -- simple vs annual compounding, at a declared statutory rate. This organ REUSES the exact proleptic-Gregorian day engine from nx_sol (composition, not a re-implementation) for the day count, then does the interest in exact integer minor units. FAIL-CLOSED: a judgment date before the accrual date, a negative principal, or a negative rate returns DMG_BAD -- you never compute interest on an impossible interval. The year basis is a DECLARED constant (statutes differ: 365 vs 360); it is not buried (Rule 11). SCALE ENVELOPE (declared): principal * annual_bp * days fits i64 for principal up to ~9e10 minor units at bp<=1e4, days<=1e4. license_tier: ORIGINAL No hw writes (Rule 26). LIB.