Set node object IDs for articulated object links.

[0mdc]

Motivation and Context

This change sets the OBJECT_ID fields for articulated object nodes.

Notes:

• For gfx-replay use cases, the articulated object link IDs are important. They are used to match gfx-replay instances with real objects.
• For semantic rendering cases, we might want to have a separate field for the root object ID.
• Tests are missing.

How Has This Been Tested

Tested using gfx-replay (habitat-sim -> habitat-lab -> Unity).

Types of changes

• Docs change / refactoring / dependency upgrade
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have completed my CLA (see CONTRIBUTING)
• I have added tests to cover my changes.
• All new and existing tests passed.

[jturner65]

Thanks for getting this!