write-manifest quarto doesn't support Shiny Quarto documents

Summary

rsconnect write-manifest quarto always creates a static document manifest, even for Quarto documents that use server: shiny in their YAML front matter. There's no way to generate a quarto-shiny manifest via the CLI.

Details

The codebase has support for AppModes.SHINY_QUARTO internally, but the CLI doesn't expose this functionality:

• No --shiny flag on write-manifest quarto
• No auto-detection of server: shiny in the Quarto document's YAML front matter
• write-manifest shiny doesn't recognize .qmd files as valid entry points

Current workarounds

1. Use quarto publish connect instead (which does handle this correctly)
2. Manually create a manifest.json with "appmode": "quarto-shiny"

Expected behavior

Either:

• write-manifest quarto should detect server: shiny in the document and create a quarto-shiny manifest automatically, OR
• A --shiny flag should be added to explicitly request a Shiny Quarto manifest

CLI のエントリポイント write-manifest quarto と write-manifest shiny から始め、既存の AppModes.SHINY_QUARTO サポートを追跡します。Quarto YAML front matter と有効なエントリポイントがどのように扱われているかを確認します。server: shiny を使用する .qmd ドキュメントに対して、検出または明示的なフラグのいずれかによって、CLI が quarto-shiny マニフェストを生成できれば完了です。