[stable31] fix(PreviewOptions): set active radio button on open

[janbaum]

Backport for #7750

[mejo-]

@janbaum this is a good start 😊

I changed the base branch for this PR to stable31, this was missing - it was still set to main. We don't want to merge this PR into main though. That's also why it had listed so many commits.

Regarding the code changes, it's a bit mean with the linter: on stable31 we still use older versions of eslint and code style, that's why the coding conventions are different. When you check out stable31 locally, you have to run npm ci once again before running npm run lint.

A backport to a stable release should contain just the changes that you want to backport, no further changes to the file. So ideally you revert all changes to the file except the replacement of :checked=... with :model-value=....

[mejo-]

As discussed with @janbaum I took over and opened #7784 as I lack permissions to push into his repo/branch.

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