denvi/candle — reverse-engineered prompt

Build me a desktop app for running a GRBL CNC machine, similar to Candle. I want it to connect to the machine, show the current machine status, and let me control movement with on screen buttons, keyboard number pad controls, and a simple command console.

It should let me open G code files, view and edit them, save changes, and send the job to the machine. I also want a clear visual preview of the G code tool path so I can see what the machine is going to do before I run it.

Please make it a C++ Qt app that can run on Windows, Linux, macOS, and Raspberry Pi OS. Keep the interface practical and workshop friendly, with the main controls easy to find. Include basic build instructions and make sure the project can be built cleanly with CMake. Look up current Qt and GRBL docs online if you need to.