test: setup common stability and robustness properties tracking

lib/volume/vwad/Vwad.Quantower.Tests.cs

@@ -161,4 +161,4 @@ public class VwadIndicatorTests
         // Different periods should produce different results
         Assert.NotEqual(val10, val20, 6);
     }
-}
+}

lib/volume/vwad/Vwad.Tests.cs

@@ -426,4 +426,4 @@ public class VwadTests
         Assert.Equal(expected, spanResult, precision: 9);
         Assert.Equal(expected, streamingResult, precision: 9);
     }
-}
+}

lib/volume/vwad/Vwad.Validation.Tests.cs

@@ -244,4 +244,4 @@ public class VwadValidationTests
         // Most bars should cause changes (unless MFM happens to be exactly 0)
         Assert.True(changeCount > _data.Bars.Count * 0.5, "VWAD should change for most bars with non-zero MFM");
     }
-}
+}