While working on #12595, @zanieb suggested to split out the design for calls-to-action for unsafe fixes and display-only fixes, since it is not obvious what the design there should be. A few key points to consider:

• Should there be per-fix calls-to-action (which is what we started out with) or only a summary?
• Should unsafe fixes be displayed by default? As of the status quo at the end of Display fixes by default (#7352) #12595, the answer is “no”, but maybe they should in check mode, or perhaps there should be a flag to display all fixes. The new behavior means that there is actually no way to display those fixes without also running the fixer.
• What should the language and formatting be? Color? Bold? etc.?