Add support for custom source grouping

[pwang347]

Fixes #280798

[aeschli]

I wonder if this should be rather be done as a label on the provider.

[pwang347]

I wonder if this should be rather be done as a label on the provider.

How do you see the label being used? I guess in the current UX, we have fixed categories like Extensions, Workspace etc. On top of this broader categorization, we could have some way to filter based on the provided label maybe?

[aeschli]

I liked the way you proposed it in the screenshot. If a provider has a label, use it as category, if not, thing go to 'Extensions'. That can lead to potentially many categories so we have to see, but at least for the ones we contribute we can make sure we reuse Categories.
We might need to add the category to the existing (static) contribution points.

[pwang347]

I liked the way you proposed it in the screenshot. If a provider has a label, use it as category, if not, thing go to 'Extensions'. That can lead to potentially many categories so we have to see, but at least for the ones we contribute we can make sure we reuse Categories. We might need to add the category to the existing (static) contribution points.

I think I'd like to hold off on making the label public part of contract since like you said we can end up with a mess if each extension tries to create their own convention. We can still keep it on the provider as private? We can most likely extend the contracts as needed if/when our UX makes this distinction more useful. Let me know what you think!