FEATURE: Add api scope for search endpoint (#19955)

Adds two new api scopes for the /search endpoints:

- `/search.json?q=term`
- `/search/query.json?term=term`

see: https://meta.discourse.org/t/search-api-key-permissions/227244

spec/requests/admin/api_controller_spec.rb

@@ -428,6 +428,7 @@ RSpec.describe Admin::ApiController do
           "global",
           "badges",
           "categories",
+          "search",
           "wordpress",
         )
       end