message: uimin/uimax/uisoftmax added to UsdPreviewSurface parameters
diff: <!-- Node: UsdPreviewSurface -->
  <nodedef name="ND_UsdPreviewSurface_surfaceshader" node="UsdPreviewSurface" nodegroup="pbr" doc="USD preview surface shader" version="2.3" isdefaultversion="true">
  - <input name="diffuseColor" type="color3" value="0.18, 0.18, 0.18" />
  - <input name="emissiveColor" type="color3" value="0, 0, 0" />
  + <input name="diffuseColor" type="color3" value="0.18, 0.18, 0.18" uimin="0,0,0" uimax="1,1,1" />
  + <input name="emissiveColor" type="color3" value="0, 0, 0" uimin="0,0,0" uisoftmax="1,1,1" />
  <input name="useSpecularWorkflow" type="integer" value="0" />
  - <input name="specularColor" type="color3" value="0, 0, 0" />
  - <input name="metallic" type="float" value="0" />
  - <input name="roughness" type="float" value="0.5" />
  - <input name="clearcoat" type="float" value="0" />
  - <input name="clearcoatRoughness" type="float" value="0.01" />
  - <input name="opacity" type="float" value="1" />
  - <input name="opacityThreshold" type="float" value="0" />
  - <input name="ior" type="float" value="1.5" />
  + <input name="specularColor" type="color3" value="0, 0, 0" uimin="0,0,0" uimax="1,1,1" />
  + <input name="metallic" type="float" value="0" uimin="0.0" uimax="1.0" />
  + <input name="roughness" type="float" value="0.5" uimin="0.0" uimax="1.0" />
  + <input name="clearcoat" type="float" value="0" uimin="0.0" uimax="1.0" />
  + <input name="clearcoatRoughness" type="float" value="0.01" uimin="0.0" uimax="1.0" />
  + <input name="opacity" type="float" value="1" uimin="0.0" uimax="1.0" />
  + <input name="opacityThreshold" type="float" value="0" uimin="0.0" uimax="1.0" />
  + <input name="ior" type="float" value="1.5" uimin="0.0" uisoftmax="3.0" />
  <input name="normal" type="vector3" value="0, 0, 1" />
  <input name="displacement" type="float" value="0" />
  - <input name="occlusion" type="float" value="1" />
  + <input name="occlusion" type="float" value="1" uimin="0.0" uimax="1.0" />
  <output name="out" type="surfaceshader" />
  </nodedef>
  