Adapting an S6 for OctoPrint

In my last project, I managed to get OctoPrint running inside Debian on my Galaxy S6. Everything was running fine, except a few small things keeping the system from being fully controllable from OctoPrint:

1) Can’t restart/shutdown phone from OctoPrint’s web interface
2) Permissions block 3D printer every time it’s reconnected
This post demonstrates the fix for the issue and some other benefits as a result.