fix: resolve ReferenceError for undefined isBlogPost in PageHead component

- Add isBlogPost as optional boolean prop to PageHead component
- Pass isBlogPost prop from NotionPage to PageHead component
- Fixes runtime error when rendering blog post structured data

components/NotionPage.tsx

@@ -297,6 +297,7 @@ export function NotionPage({
         description={socialDescription}
         image={socialImage}
         url={canonicalPageUrl}
+        isBlogPost={isBlogPost}
       />
 
       {isLiteMode && <BodyClassName className='notion-lite' />}

components/PageHead.tsx

@@ -10,12 +10,14 @@ export function PageHead({
   description,
   pageId,
   image,
-  url
+  url,
+  isBlogPost
 }: types.PageProps & {
   title?: string
   description?: string
   image?: string
   url?: string
+  isBlogPost?: boolean
 }) {
   const rssFeedUrl = `${config.host}/feed`