feat(ao-histogram): add Awesome Oscillator Histogram

AO - SMA(AO, sma_period). A configurable variant of the existing
AcceleratorOscillator (which fixes fast=5, slow=34, sma=5).
Three parameters; defaults match Bill Williams' Accelerator.

Touchpoints: awesome_oscillator_histogram.rs + mod.rs + lib.rs
re-export, PyAoHist + __init__.py + test_new_indicators CANDLE_SCALAR
+ test_known_values flat reference, AwesomeOscillatorHistogramNode +
index.d.ts/index.js + indicators.test.js factory + reference,
WasmAoHist, candle-fuzz target, README + CHANGELOG.

bindings/node/__tests__/indicators.test.js

@@ -102,6 +102,7 @@ const candleScalar = {
   MedianPrice: { make: () => new wickra.MedianPrice(), step: (ind, i) => ind.update(high[i], low[i]), batch: (ind) => ind.batch(high, low) },
   WeightedClose: { make: () => new wickra.WeightedClose(), step: (ind, i) => ind.update(high[i], low[i], close[i]), batch: (ind) => ind.batch(high, low, close) },
   AcceleratorOscillator: { make: () => new wickra.AcceleratorOscillator(5, 34, 5), step: (ind, i) => ind.update(high[i], low[i]), batch: (ind) => ind.batch(high, low) },
+  AwesomeOscillatorHistogram: { make: () => new wickra.AwesomeOscillatorHistogram(5, 34, 5), step: (ind, i) => ind.update(high[i], low[i]), batch: (ind) => ind.batch(high, low) },
   BalanceOfPower: { make: () => new wickra.BalanceOfPower(), step: (ind, i) => ind.update(open[i], high[i], low[i], close[i]), batch: (ind) => ind.batch(open, high, low, close) },
   ChoppinessIndex: { make: () => new wickra.ChoppinessIndex(14), step: (ind, i) => ind.update(high[i], low[i], close[i]), batch: (ind) => ind.batch(high, low, close) },
   TrueRange: { make: () => new wickra.TrueRange(), step: (ind, i) => ind.update(high[i], low[i], close[i]), batch: (ind) => ind.batch(high, low, close) },
@@ -260,6 +261,16 @@ test('LinRegAngle of a unit-slope series is 45 degrees', () => {
   assert.ok(Math.abs(out[4] - 45) < 1e-9);
 });
 
+test('AwesomeOscillatorHistogram on a flat median converges to zero', () => {
+  const n = 50;
+  const out = new wickra.AwesomeOscillatorHistogram(3, 5, 3).batch(
+    Array(n).fill(11),
+    Array(n).fill(9),
+  );
+  // warmup = 5 + 3 - 1 = 7.
+  for (let i = 6; i < n; i++) assert.ok(Math.abs(out[i]) < 1e-12);
+});
+
 test('APO(3, 5) on a flat series converges to zero', () => {
   const out = new wickra.APO(3, 5).batch(Array(30).fill(42));
   for (let i = 0; i < 4; i++) assert.ok(Number.isNaN(out[i]));

bindings/node/index.js

@@ -310,7 +310,7 @@ if (!nativeBinding) {
   throw new Error(`Failed to load native binding`)
 }
 
-const { version, SMA, EMA, WMA, RSI, DEMA, TEMA, HMA, ROC, TRIX, SMMA, TRIMA, ZLEMA, MOM, CMO, DPO, StdDev, UlcerIndex, VerticalHorizontalFilter, ZScore, MACD, BollingerBands, ATR, Stochastic, OBV, ADX, CCI, WilliamsR, MFI, PSAR, Keltner, Donchian, VWAP, RollingVWAP, AwesomeOscillator, Aroon, KAMA, APO, T3, TSI, PMO, ADL, VolumePriceTrend, ChaikinMoneyFlow, ChaikinOscillator, ForceIndex, EaseOfMovement, SuperTrend, ChandelierExit, ChandeKrollStop, AtrTrailingStop, TypicalPrice, MedianPrice, WeightedClose, LinearRegression, LinRegSlope, AcceleratorOscillator, BalanceOfPower, ChoppinessIndex, TrueRange, ChaikinVolatility, LinRegAngle, BollingerBandwidth, PercentB, NATR, HistoricalVolatility, AroonOscillator, Vortex, MassIndex, StochRSI, UltimateOscillator, PPO, Coppock, VWMA } = nativeBinding
+const { version, SMA, EMA, WMA, RSI, DEMA, TEMA, HMA, ROC, TRIX, SMMA, TRIMA, ZLEMA, MOM, CMO, DPO, StdDev, UlcerIndex, VerticalHorizontalFilter, ZScore, MACD, BollingerBands, ATR, Stochastic, OBV, ADX, CCI, WilliamsR, MFI, PSAR, Keltner, Donchian, VWAP, RollingVWAP, AwesomeOscillator, Aroon, KAMA, APO, AwesomeOscillatorHistogram, T3, TSI, PMO, ADL, VolumePriceTrend, ChaikinMoneyFlow, ChaikinOscillator, ForceIndex, EaseOfMovement, SuperTrend, ChandelierExit, ChandeKrollStop, AtrTrailingStop, TypicalPrice, MedianPrice, WeightedClose, LinearRegression, LinRegSlope, AcceleratorOscillator, BalanceOfPower, ChoppinessIndex, TrueRange, ChaikinVolatility, LinRegAngle, BollingerBandwidth, PercentB, NATR, HistoricalVolatility, AroonOscillator, Vortex, MassIndex, StochRSI, UltimateOscillator, PPO, Coppock, VWMA } = nativeBinding
 
 module.exports.version = version
 module.exports.SMA = SMA
@@ -350,6 +350,7 @@ module.exports.AwesomeOscillator = AwesomeOscillator
 module.exports.Aroon = Aroon
 module.exports.KAMA = KAMA
 module.exports.APO = APO
+module.exports.AwesomeOscillatorHistogram = AwesomeOscillatorHistogram
 module.exports.T3 = T3
 module.exports.TSI = TSI
 module.exports.PMO = PMO

bindings/node/src/lib.rs

@@ -1068,6 +1068,58 @@ impl AroonNode {
     }
 }
 
+#[napi(js_name = "AwesomeOscillatorHistogram")]
+pub struct AwesomeOscillatorHistogramNode {
+    inner: wc::AwesomeOscillatorHistogram,
+}
+#[napi]
+impl AwesomeOscillatorHistogramNode {
+    #[napi(constructor)]
+    pub fn new(fast: u32, slow: u32, sma_period: u32) -> napi::Result<Self> {
+        Ok(Self {
+            inner: wc::AwesomeOscillatorHistogram::new(
+                clamp_period(fast),
+                clamp_period(slow),
+                clamp_period(sma_period),
+            )
+            .map_err(map_err)?,
+        })
+    }
+    #[napi]
+    pub fn update(&mut self, high: f64, low: f64) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(cnd(high, low, low, 0.0)?))
+    }
+    #[napi]
+    pub fn batch(&mut self, high: Vec<f64>, low: Vec<f64>) -> napi::Result<Vec<f64>> {
+        if high.len() != low.len() {
+            return Err(NapiError::from_reason(
+                "high and low must be equal length".to_string(),
+            ));
+        }
+        let mut out = Vec::with_capacity(high.len());
+        for i in 0..high.len() {
+            out.push(
+                self.inner
+                    .update(cnd(high[i], low[i], low[i], 0.0)?)
+                    .unwrap_or(f64::NAN),
+            );
+        }
+        Ok(out)
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
 #[napi(js_name = "APO")]
 pub struct ApoNode {
     inner: wc::Apo,