Refactor error handling and calculations in TheilU, Wmape, and TukeyBiweight classes; update buffer handling for consistency

- Updated buffer handling in TheilU and Wmape classes to ensure consistency after adding new values.
- Changed the resync interval constant in TukeyBiweight for better clarity.
- Refactored state structures to record structs in Gauss, Hann, Hp, Hpf, Kalman, Loess, Notch, and other filter classes for improved performance and readability.
- Enhanced numerical stability in Mama class calculations using Fused Multiply-Add (FMA) for precision.
- Added comprehensive tests for Atan2 validation to compare .NET's Math.Atan2 with PineScript's implementation, ensuring accuracy across various edge cases.
- Updated NDepend badges to reflect changes in classes, methods, and lines of code.

lib/channels/vwapsd/Vwapsd.Quantower.cs

@@ -52,8 +52,7 @@ public class VwapsdIndicator : Indicator, IWatchlistIndicator
 
     protected override void OnUpdate(UpdateArgs args)
     {
-        var item = HistoricalData[Count - 1, SeekOriginHistory.Begin];
-        var time = HistoricalData.Time();
+        var item = HistoricalData[0, SeekOriginHistory.End];
 
         // VWAP requires OHLCV data - using HLC3 for price
         double high = item[PriceType.High];
@@ -61,7 +60,7 @@ public class VwapsdIndicator : Indicator, IWatchlistIndicator
         double close = item[PriceType.Close];
         double volume = item[PriceType.Volume];
 
-        TBar bar = new(time, item[PriceType.Open], high, low, close, volume);
+        TBar bar = new(item.TimeLeft, item[PriceType.Open], high, low, close, volume);
         TValue result = vwapsd!.Update(bar, args.IsNewBar());
 
         VwapSeries!.SetValue(result.Value, vwapsd.IsHot, ShowColdValues);

lib/channels/vwapsd/Vwapsd.Tests.cs

@@ -325,6 +325,37 @@ public class VwapsdTests
         Assert.NotEqual(vwapBeforeReset, vwapsd.Vwap.Value);
     }
 
+    [Fact]
+    public void Vwapsd_SessionReset_ResetsIsHotGating()
+    {
+        var vwapsd = new Vwapsd(1.0);
+        var gbm = new GBM(startPrice: 100.0, mu: 0.02, sigma: 0.1, seed: 42);
+        var bars = gbm.Fetch(20, DateTime.UtcNow.Ticks, TimeSpan.FromMinutes(1));
+
+        // Process bars until IsHot is true (WarmupPeriod = 2)
+        vwapsd.Update(bars[0]);
+        Assert.False(vwapsd.IsHot);
+        vwapsd.Update(bars[1]);
+        Assert.True(vwapsd.IsHot);
+
+        // Process more bars to ensure we're well past warmup
+        for (int i = 2; i < 10; i++)
+        {
+            vwapsd.Update(bars[i]);
+        }
+        Assert.True(vwapsd.IsHot);
+
+        // Reset session - IsHot should become false
+        var resetBar1 = new TBar(DateTime.UtcNow, 200, 210, 190, 200, 1000);
+        vwapsd.Update(resetBar1, isNew: true, reset: true);
+        Assert.False(vwapsd.IsHot, "IsHot should be false after reset (1 bar accumulated)");
+
+        // Process second bar after reset - IsHot should become true
+        var resetBar2 = new TBar(DateTime.UtcNow.AddMinutes(1), 205, 215, 195, 205, 1100);
+        vwapsd.Update(resetBar2, isNew: true);
+        Assert.True(vwapsd.IsHot, "IsHot should be true after 2 bars accumulated post-reset");
+    }
+
     [Fact]
     public void Vwapsd_VwapFormula_MatchesExpected()
     {

lib/channels/vwapsd/Vwapsd.Validation.Tests.cs

@@ -106,12 +106,12 @@ public sealed class VwapsdValidationTests : IDisposable
                 streamingLower.Add(streamingVwapsd.Lower.Value);
             }
 
-            // Span mode - using HLC3 for price
+            // Span mode - using bar.HLC3 for price to match streaming mode
             double[] price = new double[bars.Count];
             double[] volume = new double[bars.Count];
             for (int i = 0; i < bars.Count; i++)
             {
-                price[i] = (bars[i].High + bars[i].Low + bars[i].Close) / 3.0;
+                price[i] = bars[i].HLC3;
                 volume[i] = bars[i].Volume;
             }
 

lib/channels/vwapsd/Vwapsd.cs

@@ -132,8 +132,7 @@ public sealed class Vwapsd : AbstractBase
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public TValue Update(TBar bar, bool isNew = true, bool reset = false)
     {
-        double hlc3 = (bar.High + bar.Low + bar.Close) / 3.0;
-        return Update(new TValue(bar.Time, hlc3), bar.Volume, isNew, reset);
+        return Update(new TValue(bar.Time, bar.HLC3), bar.Volume, isNew, reset);
     }
 
     /// <summary>
@@ -168,6 +167,9 @@ public sealed class Vwapsd : AbstractBase
         // Handle reset
         if (reset || !_state.IsInitialized)
         {
+            // Reset warmup tracking for proper IsHot gating after session reset
+            _index = 1;
+
             if (vol > 0)
             {
                 _state = _state with