Windows terminal wallpaper tool

Tool for setting background image properties and terminal opacity for Windows Terminal. Tested mostly on Preview version of Windows terminal.
WARNING: the tool currently works only for one standard of the configuration JSON. It updates 'profiles' -> 'default' clause.

Features:

• changing the background image
• changing the properties of the background image:
  • opacity
  • alignment
  • stretch mode
• changing opacity of the terminal
• choosing which terminal version should be updated (if none chosen, it will try to update the first settings file it sees):
  • stable
  • preview
  • unpackaged

Read more about those properties in Microsoft docs - https://learn.microsoft.com/en-us/windows/terminal/customize-settings/profile-appearance#background-images-and-icons

Possible todos

• better error handling
• change message level flag into flags with practial names and make them exclusionary to each other
• feature: choose image at random from the list or a folder specified
• feature: for flag without argument - show the respective property current value
• feature: saving and loading properties of an image (opacity, stretch mode, alignment) used in the past in order to remove the need for repeated property adjustment
• make the tool handle any Windows Terminal config standard
• more test coverage