chore: Group URLs in Select component

[cristianoventura]

Description

This PR maps the list of allowed requests into a dropdown, so the user can select a URL when defining a new threshold.

How to Test

• Type the konami code and enable the Thresholds feature
• Open the Generator > Test Options > Thresholds
• Check that the URL dropdown contains a list of URLs group by host, similar to the Test Builder
• Change the form to a valid state and check the console for the result
• Validations are not yet in place

Checklist

• I have performed a self-review of my code.
• I have added tests for my changes.
• I have run linter locally (npm run lint) and all checks pass.
• I have run tests locally (npm test) and all tests pass.
• I have commented on my code, particularly in hard-to-understand areas.

Screenshots (if appropriate):

Related PR(s)/Issue(s)

[Llandy3d]

Seems to work well 🙌

A created threshold disappears on closing and reopening the popover but maybe it's expected at this stage.

I would also consider calling the last field in the table STOP TEST like in the cloud or adding a tooltip because on its own it seem confusing being just stop 🤔

[going-confetti]

Semantically, those will still be disabled options, rather than groups.
I suggest one of the following options instead:

• StyledReactSelect that @e-fisher added recently? It's a wrapper around react-select, which supports groups out of the box.
• Use <Select.Group> for groups

[cristianoventura]

@going-confetti I've had some issues with ControlledReactSelect (which implements StyledReactSelect) inside the PopoverDialog. The positioning doesn't work well and when trying to use a portal to render it somewhere else, most of the styles were lost, so I followed your second option here by adding support to Select.Group in the existing ControlledSelect component.

[going-confetti]

IMO this should have the same font size as the options, otherwise it looks inconsistent. Though this comment will likely be irrelevant once the other one has been resolved

[cristianoventura]

A created threshold disappears on closing and reopening the popover but maybe it's expected at this stage.

@Llandy3d This is expected at this point, but will be fixed soon ⚔️ 🐛

I would also consider calling the last field in the table STOP TEST like in the cloud or adding a tooltip because on its own it seem confusing being just stop 🤔

I'll do a UI polishment before promoting the feature and made notes of this to address later on! 👍

[going-confetti]

LGTM!