Radio buttons: Selected radio button should/could have a border to improve UI

[ ] I have written a good issue

Describe the enhancement

I would like a selected radio button to stand out more clear. On a white background or a card it is hard to see the white border, making the selected radio button harder to spot. In general it also creates a disharmoni in balance on grey or white backgrounds, as it appears smaller than the unselected buttons.

Describe the solution you'd like

I would like to add/keep the grey border that unselected have.

Have you considered any alternatives?

Are there any additional context?

Checklist:

The following tasks should be carried out in sequence in order to follow the process of contributing correctly.

Refinement

[ ] Request that the issue is UX refined
[ ] Request that the issue is tech refined; do not proceed until this is done.

Implementation

The contributor who wants to implement this issue should:

[ ] Make sure you have read: "Before you get coding".
[ ] Signal to others you are working on the issue by assigning yourself.
[ ] Create a branch from the develop branch following our branch naming convention.
[ ] Publish a WIP implementation to Github as a draft PR and ask for feedback.
[ ] Make sure you have implemented tests following the guidelines in: "The good: Test".
[ ] Update the cookbook with examples and showcases.

Review

Once the issue has been implemented and is ready for review:

[ ] Do a self-review.
[ ] Create a pull-request. If you created a draft PR during implementation you can just mark that as "ready for review".

kirbydesign / designsystem