Subdue container labels to distinguish them from space views

[abey79]

What

As the title says ☝🏻. Note that the icon still reflects visibility.

Here, the tab widget is visible but not the vertical one:

Selection panel (which currently doesn't reflect visibility state #4854):

Relates to:

• Make blueprint tree more scannable, and the concepts clearer by distinguishing containers, space views, and entities. #4743

Note: this PR piles on debt to be paid off with:

• Remove all formatting API from ListItem and use WidgetText's API instead #4802

Checklist

• I have read and agree to Contributor Guide and the Code of Conduct
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  • Using newly built examples: app.rerun.io
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[nikolausWest]

I don't think this design really worked. It's too hard to distinguish and greying out just the names didn't really communicate that there is something different about this kind of thing

[abey79]

I don't think this design really worked. It's too hard to distinguish and greying out just the names didn't really communicate that there is something different about this kind of thing

I agree. I'm not really sure how to go forward from this. Color? That's how macOS/windows deals with that: coloured, very strongly styled icons for containers.

Any icon sub-typing is very discreet:

@martenbjork help! 😅

[teh-cmc]

Should we draft this?

[abey79]

Should we draft this?

We actually decided to discard it.