feat: VS Code/Cursor を対話式で選択可能に

[striderkein]

Summary

• vscode_install.sh で VS Code と Cursor のどちらかを対話式で選択できるように変更
• 選択に応じて設定ファイルのパスと CLI コマンドを切り替え

Test plan

• スクリプトを実行して「1」を選択 → VS Code の設定が更新されることを確認
• スクリプトを実行して「2」を選択 → Cursor の設定が更新されることを確認
• 無効な入力（例: 3）でエラーメッセージが表示されることを確認

Closes #26

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Note

Enables interactive selection of editor and applies settings/extensions accordingly.

• Prompts user in vscode_install.sh to choose VS Code or Cursor, setting SETTING_DIR and EDITOR_CMD based on choice
• Links settings.json and keybindings.json to the chosen editor's User directory and prints status
• Uses the selected CLI (code or cursor) to install extensions from extensions and to refresh the list
• Adds CLI existence check with tailored install instructions; exits on invalid choice
• Removes hardcoded VS Code paths/commands in favor of generalized variables

^{Written by Cursor Bugbot for commit fd662b2. This will update automatically on new commits. Configure here.}

[cursor]

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[cursor]

Shared extensions file causes cross-editor contamination

Medium Severity

The script reads from and writes to a single shared extensions file for both VS Code and Cursor. When a user runs the script for one editor, it overwrites the extensions file with that editor's installed extensions. Running the script later for the other editor will use the wrong extension list and then overwrite it again. This causes unintended cross-contamination between the two editors' extension configurations.

Additional Locations (1)

• vscode-dotfiles/vscode_install.sh#L50-L54