refactor: ♻️ Reference item to html function update

Author: uttamukkoji

src/json-to-html.ts

@@ -108,7 +108,7 @@ export function referenceToHTML(node: Node,
     if (!entry) {
         return ''
     }
-    const metadata = nodeToMetadata(node.attrs, node.children.length > 0 ? node.children[0] as unknown as TextNode : undefined)
+    const metadata = nodeToMetadata(node.attrs, ((node.children && node.children.length > 0) ? node.children[0]: {}) as unknown as TextNode)
     metadata.item = findEmbeddedItems(metadata, entry)[0]
     return findRenderString(metadata, renderOption)
 }

src/nodes/node-type.ts

@@ -30,7 +30,8 @@ enum NodeType {
     BLOCK_QUOTE = 'blockquote',
     CODE = 'code',
 
-    TEXT = 'text'
+    TEXT = 'text',
+    REFERENCE = 'reference'
 }
 
 export default NodeType;