Introduce custom select component

[msujew]

What it does

Closes #8153

Introduces a custom react component for rendering select elements. It mirrors mostly how a native html select element works and allows for some additional features like element descriptions, details, separators, etc.

Mostly get's used for preference enum rendering, but I've also replaced some other select elements throughout the app.

How to test

In general, test that the component works just like the VSCode select element for enum preferences, launch debug config selection, etc.

1. Open the preference widget and play around with the different enum preferences. Also try to open preferences which are near the bottom of the app and observe that the dropdown gets inverted.
2. The component should react as expected when clicking on other elements or scrolling
3. The debug toolbar also uses the component. Confirm that every option is always rendered on a single line, expanding the dropdown width as necessary.

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• As a reviewer, I agree to behave in accordance with the review guidelines

[colin-grant-work]

Overall, looking pretty awesome. This is something I've been looking forward to / meaning to do for a while, so I'm really excited to see it!

(PS: everything I say about VSCode's behavior applies in the preference case - I haven't checked the other use cases as thoroughly)

[vince-fugnitto]

The changes look really great and are a very nice improvement to the framework 👍

I do not have any feedback for the code itself at the time, I mostly tested the functionality and each dropdown, especially how the changes enhance the UX of the preferences-view and now display enumDescriptions.

The only minor UI improvement I could see at the time is to reduce the separator height, which can be seen with debug configurations dropdown:

It is debatable however if you believe the thicker border looks better than the behavior we see in vscode.

[msujew]

@vince-fugnitto I think you're right. I reduced the separator thickness to 1px and reduced the margin as well to make everything a bit more compact 👍

[vince-fugnitto]

The changes look good, and work well for me 👍

[msujew]

@colin-grant-work I would merge this within the next few days. Any other comments from your side?

[colin-grant-work]

Looks great. Very nice work @msujew!