feat: add last modified date display and clean up imports in documentation pages

- Integrated the lastModified plugin to show the last updated date on documentation pages.
- Cleaned up duplicate imports in the page component for improved code clarity.

Author: kWAYTV

apps/fumadocs/source.config.ts

@@ -4,6 +4,7 @@ import {
   frontmatterSchema,
   metaSchema,
 } from "fumadocs-mdx/config";
+import lastModified from "fumadocs-mdx/plugins/last-modified";
 
 // You can customise Zod schemas for frontmatter and `meta.json` here
 // see https://fumadocs.dev/docs/mdx/collections
@@ -21,6 +22,7 @@ export const docs = defineDocs({
 });
 
 export default defineConfig({
+  plugins: [lastModified()],
   mdxOptions: {
     // MDX options
   },

apps/fumadocs/src/app/docs/[[...slug]]/page.tsx

@@ -36,6 +36,12 @@ export default async function Page(props: PageProps) {
           })}
         />
 
+        {page.data.lastModified && (
+          <p className="text-muted-foreground text-sm">
+            Updated: {page.data.lastModified.toLocaleDateString()}
+          </p>
+        )}
+
         <div className="flex flex-row items-center gap-2 border-b pt-2 pb-6">
           <LLMCopyButton markdownUrl={`${page.url}.mdx`} />
           <ViewOptions