Shell Script to start print

Hello, one thing that has annoyed me about Octoprint is that I need to use my computer/phone to control the printer. Due to this, I have started using Marlin's CUSTOM_USER_MENUS function and some action commands to be able to pause/resume and cancel the print right from the printers LCD screen. However, one glaring function I am missing is start print. I have been looking at this plugin which would allow me to run customs shell scripts when I send a command from the printer. What I would want to do is create a Shell script that starts printing the latest uploaded file. I have looked but I haven't found any shell scripts to start a print. If someone had any ideas on how this script could look that would be very helpful!

POST /api/job HTTP/1.1
Content-Type: application/json
X-Api-Key: abcdef...

  "command": "start"

Thank you, will try that!