FIX: Respect default category sort when filter=default (#23411)

Previously we would respect it if the filter was `nil`, but if `default` was explicitly passed then it would ignore the category order settings. This explicit passing of `filter=default` happens for some types of navigations in the JS app.

This extends the fix from 92bc61b

lib/topic_query.rb

@@ -749,7 +749,7 @@ def default_results(options = {})
         # category default sort order
         sort_order, sort_ascending =
           Category.where(id: category_id).pick(:sort_order, :sort_ascending)
-        if sort_order && (filter.blank? || %w[latest unseen].include?(filter.to_s))
+        if sort_order && (filter.blank? || %w[default latest unseen].include?(filter.to_s))
           options[:order] = sort_order
           options[:ascending] = !!sort_ascending ? "true" : "false"
         else

spec/lib/topic_query_spec.rb

@@ -1005,6 +1005,17 @@ class ::TopicQuery
         expect(topic_ids - [topic_category.id]).to eq([topic_in_cat1.id, topic_in_cat2.id])
       end
 
+      it "uses the category's default sort order when filter=default is passed explicitly" do
+        category.update!(sort_order: "created", sort_ascending: true)
+        topic_ids =
+          TopicQuery
+            .new(user, category: category.id, filter: "default")
+            .list_latest
+            .topics
+            .map(&:id)
+        expect(topic_ids - [topic_category.id]).to eq([topic_in_cat1.id, topic_in_cat2.id])
+      end
+
       it "should apply default sort order to latest and unseen filters only" do
         category.update!(sort_order: "created", sort_ascending: true)