finance-solution 0.5.0

Finance math: TVM, cashflow, amortization, equity path metrics, technical analysis (SMA/EMA/WMA/HMA/RMA/DEMA/TEMA/KAMA/MACD/BB/Keltner/Donchian/Stoch/VWAP/RVOL/RSI/ATR/LinReg/WillR/OBV/CCI/ADX/MOM/MFI/Supertrend/SAR), risk (Sharpe/Sortino/Calmar/Ulcer/IR), and options (BSM, Black76, GK, CRR American) with Result-only APIs and incremental state.