docs: fix wrong import

Author: BearToCode

docs/src/routes/getting-started/+page.server.ts

@@ -100,7 +100,7 @@ const codeBlocks = {
 		code: deindent`
     <!-- +page.svelte -->
     <script lang="ts">
-      import PreRendered from 'carta-md';
+      import { PreRendered } from 'carta-md';
 
       let data = $props();
     </script>