Consistent API for `quiet` and other variants.

### Code of conduct

- [X] I agree to follow this project's code of conduct.

### Description of issue

On ``, quiet styling is set with the `quiet` boolean property but, on `` quiet styling is set via `variant="quiet"`. This feels like an inconsistency in our API. We should review how we're applying quiet and other variants across our components and work toward some consistency.

Start by comparing the public APIs of and , focusing on how quiet styling and other variants are expressed. Review the corresponding component entry points and their usage across the project. Done requires an agreed, consistently applied API for quiet and related variants, but the issue does not define that target.

Written by the indexing model from the issue text.