Get electron app to call our whisper script in build

[harrislapiroff]

As part of our build process we will need to bundle our whisper script in backend/stagewhisper/__main__.py into an executable inside of the electron app. We probably will use PyInstaller, PyOxidizer, or a similar utility to create the executable. The fully-built electron app should then be able to call that executable without reliance on any particular software being available on the host machine—our application should be fully self-encapsulated.

@crazy4pi314 Please feel free to elaborate on anything I've gotten wrong here or with more specifics of how we need to accomplish this for our Beta release.

[petersterne]

How is this different from #66?