It seems strange to try and make a sandboxed tool to perform work which is not sandboxed at all... There is a class of macOS applications which can perform suc

It seems strange to try and make a sandboxed tool to perform work which is not sandboxed at all... There is a class of macOS applications which can perform such functions and they're called Packages or Distributions (it's the wizard you see sometimes when an app needs to make changes to the system before you can use it). That's the way to deliver such applications from a downloadable source. Packages can be signed and notarised and none of the crazy workarounds listed in the post will be necessary.