test: finish diagnostic classification

tests/AcDream.Core.Tests/Physics/Issue265SteepSlopeCaptureBisectTests.cs

@@ -360,6 +360,7 @@ public class Issue265SteepSlopeCaptureBisectTests
     /// the correct future regression assertion) is still being decided.
     /// </summary>
     [Fact]
+    [Trait("Purpose", "Diagnostic")]
     public void RealCapturedRoofLanding_CharacterizeCurrentBehavior()
     {
         PhysicsDiagnostics.ResetForTest();