feat: handle blank value for author name

Author: ElliottAYoung

app/cells/plugins/core/author/input.haml

@@ -2,4 +2,4 @@
   = render_field_id
   = render_label
   = render_input
-  = render_hidden_value
+  = render_default_value

app/cells/plugins/core/author_cell.rb

@@ -21,7 +21,7 @@ def render_input
         @options[:form].text_field 'data[author_name]', value: value, placeholder: @options[:placeholder], class: 'mdl-textfield__input', required: required?
       end
 
-      def render_hidden_value
+      def render_default_value
         @options[:form].hidden_field 'data[default_author_name]', value: current_user.fullname
       end
     end

app/models/author_field_type.rb

@@ -1,10 +1,11 @@
-class XAuthorFieldType < FieldType
+class AuthorFieldType < FieldType
   attr_accessor :author_name
   jsonb_accessor :data, author_name: :string
 
   validates :author_name, presence: true, if: :validate_presence?
 
   def data=(data_hash)
+    data_hash[:author_name] = data_hash[:default_author_name] if data_hash.deep_symbolize_keys[:author_name].blank?
     @author_name = data_hash.deep_symbolize_keys[:author_name]
   end