Styles for "eyebrow" text in the site header

[knice]

Text above the site title in the site header region is meant to indicate affiliation between the site you are on and its parent organizations. The placement of this text above the site title reinforces the hierarchy of the campus structure. In the example above, that shows as UCSC > Social Sciences division > Economics department.

Because this region is meant for identification and wayfinding, we need to ensure that affiliation eyebrows have a consistent design.

1. finalize the design of text above a site name
2. Add styles to theme for it
3. Implement as a block editor style for a particular block, or as an alternate header pattern that can be chosen in the site editor