Create a render ast node type.

src/intermediate/plain_list_item.rs

@@ -4,7 +4,7 @@ use super::registry::Registry;
 use super::IElement;
 use super::IObject;
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub(crate) struct IPlainListItem {
     pub(crate) tag: Vec<IObject>,
     pub(crate) children: Vec<IElement>,