Implement status and discussion count on designs

Problem to solve

As a user, when I click on the design tab, it's difficult for me to tell what has been changed. When comments are left on Designs or Designs have been changed or added there is currently no way for users to know what's different in each version. There is also no information about how many comments may have been left on an individual design which means users aren't sure which design they need to respond to.

Proposal

On the Designs tab additional information should be added that alerts users to changes or additions within a certain version. Information regarding the number of comments in an issue should also be provided so that users are informed of discussions happening.

The following mockup is scoped to a user who has clicked on the Design tab and has three designs. The second design is new, as indicated by the green + box, and the third design been modified from a previous version as indicated by the blue dot.

Further details

This is part of issue https://gitlab.com/gitlab-org/gitlab-ee/issues/9491

Status Icon The CSS and HTML structure were added in MR https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/14601

The backend data needs to be made available and then hooked up to the existing frontend elements.