The problem of polyaline self intersection

Hi，
I added a polylinegraphic with a larger pixel width and transparent material. I found that when the camera is far away from the target, it overlaps itself. Why does this happen?
code:

`var viewer = new Cesium.Viewer('cesiumContainer');
viewer.entities.add({
polyline: {
positions: [Cesium.Cartesian3.fromDegrees(133,30), Cesium.Cartesian3.fromDegrees(133.5,31), Cesium.Cartesian3.fromDegrees(134,30)],
width: 50,
material: Cesium.Color.GREEN.withAlpha(0.1)
}
});
viewer.flyTo(viewer.entities);`


Start with the provided Cesium.Viewer and viewer.entities.add polyline example, reproducing the self-overlap at different camera distances with the 50-pixel transparent line. Trace the polyline rendering entry point involved in width and transparency handling; done means identifying the cause and confirming a fix or clearly documenting the rendering limitation.

Written by the indexing model from the issue text.