test: setup common stability and robustness properties tracking

lib/volume/efi/Efi.Quantower.Tests.cs

@@ -156,4 +156,4 @@ public class EfiIndicatorTests
         double val = indicator.LinesSeries[0].GetValue(0);
         Assert.True(val < 0, $"EFI should be negative on sustained price decrease, got {val}");
     }
-}
+}

lib/volume/efi/Efi.Tests.cs

@@ -334,4 +334,4 @@ public class EfiTests
         var val = efi.Update(new TBar(time.AddMinutes(1), 10, 11, 4, 5, 500));
         Assert.True(val.Value < 0);
     }
-}
+}

lib/volume/efi/Efi.Validation.Tests.cs

@@ -83,4 +83,4 @@ public class EfiValidationTests
 
         ValidationHelper.VerifyData(streamingValues.ToArray(), spanValues, 0, 100, 1e-12);
     }
-}
+}