update for direct

Author: conico974

pages/cloudflare/caching.mdx

@@ -102,7 +102,7 @@ You can customize the behaviors of the queue with environment variables:
   can use it at your own risk!
 
 - The `direct` mode for the queue is intended for debugging purposes and is not recommended for use in
-  production. We are actively working on a solution that will be suitable for production.
+  production. It only works in preview mode (i.e. `wrangler dev`)
 
 </Callout>