Upgrade iron items to diamond items

Players could upgrade iron tools, weapons, and armor to diamond using a smithing table. To do this, they would place the iron item in the smithing table, use a diamond instead of a netherite ingot, and apply the appropriate smithing template. Diamond items could then be upgraded to netherite as usual. The main purpose of this feature would be to make equipment progression more consistent. Currently, players can upgrade diamond gear to netherite while keeping all enchantments, names, and prior investment, but there is no similar path from iron to diamond. This feature would allow players to preserve valuable enchanted equipment that they have spent time, experience levels, and resources obtaining. Instead of replacing an item and rebuilding it from scratch, players could gradually improve their gear throughout their survival journey. The system would not make progression easier or cheaper, as players would still need the required diamonds and smithing template. It would simply provide a smoother and more rewarding upgrade path while maintaining the value of the player's existing equipment. And, to keep progression balanced, iron equipment could only be upgraded to diamond equipment. Players would still need to upgrade their diamond gear to netherite separately, meaning iron items could not be upgraded directly to netherite. This preserves the intended progression path while allowing players to keep and improve equipment they have already invested in.