Add 'Select All' and 'Redo' features for text editing on macOS

Add "Paste and Match Style" feature for macOS

Ensure process is defined in version check

To allow for user agents which contain "electron" within their name but do not run within a node.js context, we need to check if the process object is defined at all before accessing its properties.

In particular, this is required to run diagrams.net within a Visual Studio Code webview extension.