Is your feature request related to a problem? Please describe.
Theurgy doesn't use GUIs. It makes it hard for players to identify which items go in which machine at a glance.

Describe the solution you'd like
Make the bounding color change color depending on player's held stack.

Additional context
Shouldn't cause performance problems as this would be all client sided.

TODO:

• decide what the source of truth for green/red preview is (recipe vs actual interaction simulation)
  • source of truth should be the abstract "fit" of the item to the block
• Consider adding an additional behaviour that is called client side only before the itemhandler, this behaviour could encapsulate the below behaviour and provide the required info (red / green on one call, info message on the other).
  • only if success, call itemhandler
• switch the test implementation to use craftingbehaviour#canprocess instead of itemhandlerbehaviour to show green/red
• if it the actual interaction fails, it would be good to show why (block full), ...
  • that requires to add additional checks to the client side itemhandler behaviour or maybe to the storage behaviour
    • simulate isValid check (craftingbehaviour) -> if that fails we have the wrong item type
    • then simulate insert -> if that fails the inventory is full
• properly handle fluid container items
• handle pyromantic brazier