fix: update VITE_SERVER_URL in vercel.json to correct server address

Author: hotlong

apps/studio/vercel.json

@@ -7,9 +7,7 @@
   "build": {
     "env": {
       "VITE_RUNTIME_MODE": "server",
-      "VITE_SERVER_URL": "",
-      "TURSO_DATABASE_URL": "@turso_database_url",
-      "TURSO_AUTH_TOKEN": "@turso_auth_token"
+      "VITE_SERVER_URL": "https://play.objectstack.ai",
     }
   },
   "rewrites": [