fix: adds not found page

src/app/(payload)/admin/[[...segments]]/not-found.tsx

@@ -0,0 +1,22 @@
+/* THIS FILE WAS GENERATED AUTOMATICALLY BY PAYLOAD. */
+import type { Metadata } from 'next'
+
+import config from '@payload-config'
+/* DO NOT MODIFY IT BECAUSE IT COULD BE REWRITTEN AT ANY TIME. */
+import { NotFoundPage, generatePageMetadata } from '@payloadcms/next/views'
+
+type Args = {
+  params: {
+    segments: string[]
+  }
+  searchParams: {
+    [key: string]: string | string[]
+  }
+}
+
+export const generateMetadata = ({ params, searchParams }: Args): Promise<Metadata> =>
+  generatePageMetadata({ config, params, searchParams })
+
+const NotFound = ({ params, searchParams }: Args) => NotFoundPage({ config, params, searchParams })
+
+export default NotFound