Document how to use Atomic module

Having created a Search Component at /admin/config/search/coveo/search_components, a block became available in the block layout page with the same name as the search component.

However, when viewing the block on the front end, I'm seeing a 403 error from /rest/search/v2?organizationId={orgID} and a 400 from /rest/v15/analytics/custom?visitor={visitorID}

The merge requests for 💬 412 Precondition Failed Active and ✨ Provide a standalone search box Active add documentation that explains how to set up search components.