Task: finance-20261003-dupont-period-basis-design-fullstack (P1; proposer wecom-finance) Basis ruling: finance 2026-10-03 (Boss 09:49 CST DM approval of the design task) - /reports/dupont accepts period/start/end/annualize (default YTD), returns period_start/period_end/basis/annualized metadata; identity guard |ROE - npm x turnover x multiplier| <= 0.05 pp, else identity_broken (no values). - new app/utils/dupont_basis.py = single source of truth (window resolve, flow cumulative via voucher_details, stock average via subject_balances level=1, fail-closed basis_fallback, pure calc + identity check). - scripts/kpi_dupont_deriver.py (idempotent derived writer, dry-run/check/write), scripts/apply_dupont_kpi_defs.py + sql/dupont_kpi_defs_20261003.sql (seed: F_ASSET_TOTAL/F_EQUITY_TOTAL/F_EQUITY_MULTIPLIER as derived; F_ASSET_TURNOVER manual -> derived). Seed already applied under approval 296cc1fd. - scripts/verify_dupont_period_basis.py: read-only acceptance battery A1-A9 (independent SQL recompute). BEFORE (base tree) 1/10 PASS -> AFTER 10/13 PASS; remaining 3 need the deriver value write (approval-gated). - frontend DupontAnalysis.vue: period selector (YTD default) + annualize switch + caliber metadata bar + identity_broken alert. No DDL. No ERP direct connection (old register_dupont_kpis.py caliber dropped).
