Show code scanning findings for PRs

In the GitHub PR UI when looking at the diff view you are able to see both user-generated comments as well as code scanning alerts (see below).

Currently the extensions is able to show only the comments in-line in the editor. It would be great if this functionality could be expanded to also show code scanning alerts to make it easier for VS Code users to see where there are potential security bugs to be fixed.

拡張機能の GitHub pull request diff view と、既存の inline comment のレンダリングパスから始めます。この issue にはファイル名やテスト名がありません。pull request review data がどのように読み込まれるかを追跡し、次に code scanning alerts をコメントと並べて表示する方法を判断します。VS Code で該当する pull request の変更に対して code scanning findings が inline で表示されれば完了です。