More granular access to suppress warnings

### New feature, improvement proposal

Hello,
Currently when a class only has a default constructor that is not explicitly coded you get a warning of `"use of default constructor, which does not provide a comment"`. Currently the only way to "fix" this is to give the class a default constructor with a comment or to turn off missing warnings entirely with the `-missing ` flag which is broad and disables ALL missing things, including the ones I want.

I don't like the idea of having to put needless code in place ONLY to make a plugin happy. I would like to be able to suppress only this warning. Open to other suggestions as well.

Thanks you for your time on this project. It's really great.

Start by reproducing the warning for a class with only an implicit default constructor and trace how the existing `-missing` flag controls it. Define and document a narrower suppression setting, then add coverage showing that it suppresses this warning without disabling other missing-item warnings.

Written by the indexing model from the issue text.