test: setup common stability and robustness properties tracking

lib/volume/vwma/Vwma.Quantower.Tests.cs

@@ -190,4 +190,4 @@ public class VwmaIndicatorTests
         Assert.True(valueAfterHigh > valueAtConstant + 50,
             $"VWMA should increase as low-price bars drop out: {valueAtConstant} -> {valueAfterHigh}");
     }
-}
+}

lib/volume/vwma/Vwma.Tests.cs

@@ -452,4 +452,4 @@ public class VwmaTests
             Assert.Equal(batchResult.Values[i], streamingResults[i], 10);
         }
     }
-}
+}

lib/volume/vwma/Vwma.Validation.Tests.cs

@@ -399,4 +399,4 @@ public class VwmaValidationTests
 
         Assert.True(shortDiff < longDiff, "Short period VWMA should track price more closely");
     }
-}
+}