feat(sltt-app): automate build/updates of sltt-app for Mac

[Nathan22Miles]

With regard to builds for Mac:

• Automatically trigger build/publish process when a new push to 'main' branch is done.
• Automatically update version number and attach to app.
• Publish app to github.
• Verify auto-update process works for installed sltt-app.

[Nathan22Miles]

It might save money to use a service such as https://www.appveyor.com/ that is specifically created for app builds ... and which might have useful answers if we hit roadblocks.

CoPilot will generate a yaml file to do this on github. My epxerience with the copilot info to do this same process directly on my development machine was poor. The instructions generated did not work. I ended combinging info from several web pages, a few YouTube videos, and a Udemy course on building electron apps to finally generate a procedure that worked.

Part of the problem is that Apple keeps changing the process so CoPilot is faced with input info from a variety of points in time.

CoPilot is very useful when you are working in area where you have enough background to evaluate whether an answer is correct or not ... for people without this background CoPilot is far less helpful.