Thanks to @dceejay and @hardillb on the node-red slack who helped me with how to deliver node-red apps.
SCENARIO: I want to package up node.js + node-red + some flows + maybe some custom nodes, create an installer (executable or MSI file on Windows, might be different on IOS or Linux) and when the recipient receives the installer and runs, they now have the application and can run it on their laptop/desktop.
SOLUTION: @hardillb pointed me to this npm: https://www.npmjs.com/package/electron-node-red, and then @dceejay added a link to his derived package -- apparently only sources are available, here: https://github.com/dceejay/electron-node-red
I've only just started using this and still learning, so I cannot help you to resolve any issues you may encounter. Best of success with this if you have the same need as I have, to deliver products based on node-red to a lot of users.