dx: raise informative error when inverse_of is missing on STI (#3414)

* dx: raise informative error when `inverse_of` is missing on STI

* lint

app/controllers/avo/associations_controller.rb

@@ -117,6 +117,13 @@ def destroy
 
     def set_reflection
       @reflection = @record.class.reflect_on_association(association_from_params)
+
+      # Ensure inverse_of is present on STI
+      if !@record.class.descends_from_active_record? && @reflection.inverse_of.blank? && Rails.env.development?
+        raise "Avo relies on the 'inverse_of' option to establish the inverse association and perform some specific logic.\n" \
+          "Please configure the 'inverse_of' option for the '#{@reflection.macro} :#{@reflection.name}' association " \
+          "in the '#{@reflection.active_record.name}' model."
+      end
     end
 
     def set_attachment_class