fix: update TOC item access in DocTemplate component

- Modified the condition for accessing TOC items to ensure it handles undefined cases correctly.
- Updated the dependency array in the useMemo hook to include the entire toc object for better stability in TOC data generation.

Author: shhdgit

src/templates/DocTemplate.tsx

@@ -145,15 +145,15 @@ function DocTemplate({
   const pageType = getPageType(language, pageUrl);
   const rightTocData: TableOfContent[] | undefined = React.useMemo(() => {
     let tocItems: TableOfContent[] = [];
-    if (toc.items?.length === 1) {
+    if (toc?.items?.length === 1) {
       tocItems = toc.items![0].items || [];
     } else {
       tocItems = toc.items || [];
     }
 
     // Filter TOC based on CustomContent conditions
     return filterRightToc(tocItems, pageType, cloudPlan, language);
-  }, [toc.items, pageType, cloudPlan, language]);
+  }, [toc, pageType, cloudPlan, language]);
 
   const stableBranch = getStable(pathConfig.repo);