feat: TA-Lib parity — 19 standalone indicators (DM components, price transforms, ROC/LinReg/MACD/SAR variants, Hilbert outputs) (#148)
Closes the remaining TA-Lib function-name gap by shipping each missing or
bundled-only function as a real, standalone, fully-covered indicator. 19 new
indicators across 5 families; mod-count 295 -> 314.
### Trend & Directional — Directional Movement components
- `PlusDm` (`PLUS_DM`), `MinusDm` (`MINUS_DM`) — Wilder-smoothed ±DM.
- `PlusDi` (`PLUS_DI`), `MinusDi` (`MINUS_DI`) — `100·smoothed(±DM)/ATR`.
- `Dx` (`DX`) — `100·|+DI−−DI|/(+DI+−DI)`.
### Price Statistics
- `AvgPrice` (`AVGPRICE`) — `(O+H+L+C)/4`.
- `MidPoint` (`MIDPOINT`) — `(max+min)/2` of a scalar series over N.
- `MidPrice` (`MIDPRICE`) — `(highestHigh+lowestLow)/2` over N.
- `LinRegIntercept` (`LINEARREG_INTERCEPT`) — OLS intercept.
- `Tsf` (`TSF`) — time series forecast `a + b·period`.
### Momentum Oscillators
- `Rocp` (`ROCP`), `Rocr` (`ROCR`), `Rocr100` (`ROCR100`) — ROC ratio forms.
### Trailing Stops
- `SarExt` (`SAREXT`) — Parabolic SAR with start value, reversal offset,
separate long/short acceleration, signed output.
### Trend & Directional — MACD variants
- `MacdFix` (`MACDFIX`) — MACD fixed 12/26.
- `MacdExt` (`MACDEXT`) — MACD with a selectable moving-average type per line
(new public `MaType` enum: SMA/EMA/WMA/DEMA/TEMA/TRIMA).
### Ehlers / Cycle (DSP) — Hilbert transform outputs
- `HtPhasor` (`HT_PHASOR`) — in-phase / quadrature components.
- `HtDcPhase` (`HT_DCPHASE`) — dominant-cycle phase (degrees).
- `HtTrendMode` (`HT_TRENDMODE`) — trend (1) vs cycle (0) classification.
Each indicator ships the full chain: core + every-branch unit tests, Python /
Node / WASM bindings, fuzz coverage, README counter + family rows, CHANGELOG.
`cargo test`, doctests, `clippy -D warnings`, `npm test` and pytest all green
locally; mod-count == lib-block == README counter (314), FAMILIES total 309.
kingchenc
9eb46f144a