Camera tangent inversion on FBX Import when "Force Front XAxis" is enabled

When importing camera animation FBX files into Sequencer, enabling the "Force Front XAxis" option causes the key tangents for Rotation-Pitch (Y) to be inverted. This results in broken animation curves instead of the smooth transitions expected from the source data.

The customer has confirmed that passing the bForceFrontXAxis flag to the bNegateTangents parameter (4th argument) of ImportTransformChannelToDouble resolves the issue.

File: MovieSceneToolHelpers.cpp (around L3158)

if (DoubleChannels[4].Get())
{
    DoubleChannels[4].Get()->SetDefault(Rotation.Y);
-   ImportTransformChannelToDouble(EulerRotation[1], DoubleChannels[4].Get(), FrameRate, false, true);
+   ImportTransformChannelToDouble(EulerRotation[1], DoubleChannels[4].Get(), FrameRate, ImportFBXSettings->bForceFrontXAxis, true);
}

1. Create a new project in Unreal Editor.
2. Create a new Level Sequence in the Content Browser and open it.
3. Click the camera icon in the Sequencer toolbar to add a CineCameraActor.
4. Right-click the CineCameraActor track > Import and select the attached TEST_CAM.fbx.
5. In the Import dialog: Uncheck "Match by Name Only", Check "Force Front XAxis", then click Import.
6. Open the Curve Editor, select CineCameraActor > Rotation > Pitch, and inspect the curve.

Expected Result: The Pitch (Y) curve changes smoothly, matching the source animation.

Actual Result: The tangents are flipped, creating a "zigzag" or jagged wave pattern.

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