fix(ContourTriangulator): preserve oriented contour normals for x-axis

vtkContourTriangulator was incorrectly treating a valid 3-component normal as "unoriented"
via normal?.length < 3, which caused it to ignore the supplied plane orientation.

fixes #3243

Author: daker

Sources/Filters/General/ContourTriangulator/index.js

@@ -44,7 +44,7 @@ function triangulateContours(
   const newPolys = [];
   const incompletePolys = [];
 
-  const oriented = normal?.length < 3;
+  const oriented = normal?.length >= 3;
   vtkCCSMakePolysFromLines(
     polyData,
     firstLine,