Create a render ast node type.

src/intermediate/page.rs

@@ -39,13 +39,23 @@ impl BlogPostPage {
             ));
         }
 
-        // TODO: Get footnote definitions
+        let footnotes = {
+            let footnote_definitions: Vec<_> = registry
+                .get_footnote_ids()
+                .map(|(id, def)| (id, def.clone()))
+                .collect();
+            let mut ret = Vec::new();
+            for (id, def) in footnote_definitions.into_iter() {
+                ret.push(IRealFootnoteDefinition::new(registry, id, def).await?);
+            }
+            ret
+        };
 
         Ok(BlogPostPage {
             path,
             title: get_title(&document),
             children,
-            footnotes: Vec::new(), // TODO
+            footnotes,
         })
     }