Differentiate workspace APIs in ref docs

[ggetz]

As a follow up from #10824, this updates the doc generation process such that the list of classes is broken up based on the workspaces.

If we think it's warranted, I can also add a tag to to individual item pages. But it might be enough to list the path.

[cesium-concierge]

Thanks for the pull request @ggetz!

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  • If this change updates the public API in any way, please add a bullet point to CHANGES.md.
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  • Make sure you've updated tests to reflect your changes, added tests for any new code, and ran the code coverage tool.

Reviewers, don't forget to make sure that:

• Cesium Viewer works.
• Works in 2D/CV.

[sanjeetsuhag]

Looks great @ggetz! I think eventually we will want to include a more visible indicator of which package a class belongs to when you open its page, but that can probably wait till when we have more packages. I think this is a good start to organizing our docs.