Add a pill or other visual cue to help people confirm they are in the right docs

[KimberlyFields]

Across the doc sets for the different products, we have many duplicate titles. When a user searches for a topic, they may accidentally select a topic that's not related to their product. Suggest adding a way for writers to add a visual cue, such as a pill with the product name, next to a topic's title.

We do not want this to be a defult option for every topic. This would be used on a case-by-case basis.

[eric-schneider]

Couchbase has this in their Antora UI: https://docs.couchbase.com/server/current/n1ql/n1ql-language-reference/flex-indexes.html