Elegoo Neptune 4 Max Moonraker fix for Orca Slicer, Slic3r, Super Slicer, Prusa Slicer

This will fix moonraker (using Elegoo firmware) to support thumbnails and meta data shown in fluidd when using Orca Slicer, Slic3r, Prusa Slicer, and Super Slicer.

This code currently works on Neptune 4, Neptune 4 Pro, Neptune 4 Max, Neptune 4 Plus. Backup your existing metadata.py file before copying the new files over. Please do note that only files processed after updating will show the changes.

https://www.github.com/vbitshub/elegoo_moonraker