Remove untagged Component::descriptor()

[grtlr]

Related

• Part of Tagged components #6889.

What

Another big step towards having full tagging support in the viewer. By removing Component::descriptor() we make it harder to accidentally use untagged descriptors and therefore reduce bugs in our code, and in our users code.

This refactor goes right up to the point where we have to change our SDKs, so there is more design work to be made (via new AnyValues).

To achieve this we still rely on untagged components when implementing ComponentBatch::descriptor (left todos there).

Next steps are:

• Remove remaining untagged methods (track usage of Component::name())
• Designing new AnyValues AnyValues should use argument names to set archetype_field_name metadata #9906 for all SDKs.
• Making ComponentDescriptor::new more explicit when using untagged components or prevent untagged components all together by removing the optionals.
• Optionally getting rid of ComponentBatch (Maybe we wait for the removal of indicator components).

Dependency

• Requires: https://github.com/rerun-io/dataplatform/pull/815

[github-actions]

Web viewer built successfully. If applicable, you should also test it:

• I have tested the web viewer

Result	Commit	Link	Manifest
✅	f93b4a3	https://rerun.io/viewer/pr/10038	+nightly +main

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[Wumpf]

looks good!
interestingly this now for the first time makes "untagged" a concept in the codebase, but I figure that's how we used the term by now anyways

[grtlr]

Do you think we should come up with a different name / type?

[Wumpf]

I'm nervous about "untagged" because of the rerun-historical connotation: There was a world where we had only component name so this was truly untagged. But since 0.22 everything always has a tag, just that that tag is sometimes component-name-only. Calling component-name-only "untagged" rubs me a little bit the wrong way because compared to 0.21 it's still technically tagged. But a) that's ancient past now and b) I don't have any better idea what to call this either and it's good to give it a name!

[grtlr]

We have decided on calling these type of descriptors partial instead of untagged.