Search for Courses #4584

The courses side nav (#4583) contains a search box which will let you search within the course modules. I think we can probably use Algolia to segment the course modules into their own index that we search. Unclear if we also want these to be part of the larger site search and how we would indicate that they're different from typical docs in search results.

A few questions:

• What does it look like if the search result is empty
• What does it look like when the search result has found a match