fix(play): add auth

Author: yjl9903

playground/functions/api/state/[key].ts

@@ -11,6 +11,10 @@ export const onRequestGet = makePagesFunction(async ({ params, env }) => {
 });
 
 export const onRequestPost = makePagesFunction(async ({ params, request, env }) => {
+  if (request.headers.get('Authorization') !== 'vite-plugin-cloudflare-functions') {
+    return new Response('Unauthorized', { status: 401 });
+  }
+
   const key = params.key as string;
   const value = await request.text();
   await env.STORE.put(key, value, { expirationTtl: 300 });