React UI for creating Personalization Segments

Also link the OpenAPI docs for this :)

#3541152: Ensure segments have a weight and #3541148: Provide a locked Default segment are both in — I think that means this is unblocked? :)

Also: I believe the designs are done? 🤞 Let's get the issue summary updated 🙏

Per #3525619-5: React UI for editing segmentation rules in Personalization Segments, this blocks #3525619.

@mred9: you're working from @callumharrod's designs, right? Can you please link to the relevant ones in the issue summary? 🙏 And preferably upload >=1 screenshot from the design to make this issue easier to understand. (Also screenshots from the actual implementation when they exist, of course!)

Per #12.

Wrong link. 🙈

This ticket adds the WIP for the segment dashboard when the personalization extension is enabled. Supports the ability to create, rename, enable/disable, reorder, and delete segments. Additional refinements, such as proper modals and the rule editor, will be implemented as a separate ticket.