add creator links as attachments in activitystreams

app/models/creator.rb

@@ -50,7 +50,8 @@ def to_activitypub_object
       attributionDomains: [
         [Rails.application.default_url_options[:host], Rails.application.default_url_options[:port]].compact.join(":")
       ],
-      concreteType: "Creator"
+      concreteType: "Creator",
+      attachment: links.map { |it| {type: "Link", href: it.url} }
     }
   end
 end

spec/factories/creator.rb

@@ -4,5 +4,6 @@
     sequence(:public_id) { |n| "creator_#{n}" }
     caption { Faker::Lorem.sentence }
     notes { Faker::Lorem.paragraph }
+    links_attributes { [{url: "http://example.com"}] }
   end
 end

spec/models/creator_spec.rb

@@ -26,5 +26,9 @@
     it "includes notes in summary" do
       expect(ap[:summary]).to include creator.notes
     end
+
+    it "includes links as attachments" do
+      expect(ap[:attachment]).to include({type: "Link", href: "http://example.com"})
+    end
   end
 end