How to install Dracula theme offline without using .vsix file?

Hi, thank you for maintaining the Dracula theme.

I'm currently working in a completely air-gapped (offline) environment where internet access is strictly blocked.
Unfortunately, even the `.vsix` method doesn't work reliably in our setup due to additional restrictions.

Is there any alternative way to install the Dracula theme for Visual Studio Code completely offline — for example, by manually copying the theme files into a specific directory within the `.vscode/extensions` folder?

If possible, could you provide a step-by-step guide or recommend an approach for such an environment?

Thanks in advance.

まず、既存のインストール手順と、issue で言及されている .vscode/extensions の場所を確認します。テーマを .vsix ファイルなしでそこにインストールできるかどうかを判断し、その後、オフラインでの手順をステップごとに文書化し、エアギャップ環境での制限事項も記載します。

索引モデルが issue の本文から書いたものです。