Poll comments events when story is open

この issue には説明がありません。

The issue title suggests implementing polling for comment events when a story is open, but the body is empty. Look for existing story and comment handling code in the Elm application, likely in view or update modules. Determine how events are currently fetched and where polling logic should be added. Check for any related API endpoints or subscriptions.

索引モデルが issue の本文から書いたものです。