Sibl-gui

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- Ensured ground plane shader **matteForSecondaryRays** attribute in **Maya_VRay_Standard** and **Maya_VRay_Dome_Light** templates is set.

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- Added Jed Frechette **Blender_Cycles_Standard** template.
- Ensured directional light position is correct in **Maya_Arnold_Standard** and **Maya_Arnold_Dome_Light** templates.
- Fixed various issues in **Softimage_Arnold_Standard**, **Softimage_Arnold_Dome_Light** and **Softimage_Arnold_Lightsmith** templates to support latest **SItoA** build.

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- Ensured **Softimage_Arnold_Lightsmith** template compatibility with **SItoA 2.8.0** by removing deprecated legacy light filter code.

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- Removed **miCreateOtherOptionsNodesForURG** mel procedure call in **Maya_MR_Standard** and **Maya_MR_Lightsmith** templates.

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- Fixed color profiles issues in **Softimage_Arnold_Dome_Light** and **Softimage_Arnold_Standard** Templates.
- Implemented precise per channel color control over the IBL setup in **Softimage** Templates.

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- Fixed exception in **Softimage_VRay_Standard** Template.