Lesson refers to VS Code as an IDE

Although VS Code with extensions indeed blurs the line between a smart text editor and a fully fledged IDE, from what I have read across the software engineering industry, the general consensus is that VS Code is IDE-like with the correct extensions rather than a strict IDE. To avoid confusion, align with the wider software engineering industry and to perhaps aid clarification as to what the difference is between VS and VS Code, I think this distinction should be made in the course.

Granted, [even Microsoft are a little ambiguous](https://code.visualstudio.com/docs/supporting/faq#_what-is-the-difference-between-visual-studio-code-and-visual-studio-ide) but I think audiences would appreciate the precision.

まず、VS CodeをIDEとして扱っているレッスンのテキストを見つけ、Visual Studioとの違いを含め、その前後の説明を確認します。コースで正確な用語が使われ、VS Codeは適切な拡張機能を使うことでIDEに近いものであり、厳密なIDEとして扱うものではないことが明確になれば完了です。

索引モデルが issue の本文から書いたものです。