Found broken `/preparation-for-study/app.comflowy.com` link. Please fix!

この issue には説明がありません。

The issue reports a broken link at '/preparation-for-study/app.comflowy.com' but provides no further details. First, locate the file containing this link, likely in an MDX documentation file. Search for the link path in the repository. Once found, verify the correct URL and update it. Check for any related documentation or link-checking scripts to ensure the fix is correct.

索引モデルが issue の本文から書いたものです。