test: setup common stability and robustness properties tracking

lib/volatility/hlv/Hlv.Quantower.Tests.cs

@@ -301,4 +301,4 @@ public class HlvIndicatorTests
         Assert.True(double.IsFinite(val));
         Assert.True(val < 0.001, "Constant price should produce near-zero volatility");
     }
-}
+}

lib/volatility/hlv/Hlv.Tests.cs

@@ -646,4 +646,4 @@ public class HlvTests
     }
 
     #endregion
-}
+}

lib/volatility/hlv/Hlv.Validation.Tests.cs

@@ -644,4 +644,4 @@ public class HlvValidationTests
         double mean = values.Average();
         return values.Average(v => Math.Pow(v - mean, 2));
     }
-}
+}