style: fix code formatting and remove unused imports

- Fix indentation in Preview.tsx and normalize quotes
- Remove unused import in selectStarterTemplate.ts
- Improve code readability in api.github-template.ts

app/routes/webcontainer.connect.$id.tsx

@@ -29,4 +29,4 @@ export const loader: LoaderFunction = async ({ request }) => {
   return new Response(htmlContent, {
     headers: { 'Content-Type': 'text/html' },
   });
-};
+};