When the workbench has a plan show a ticker of how many items a player wants to craft where 0 is disabled.
When shift clicking if ticker > 0 every craft tick it down one and attempt to craft again until 0. This ticker will be stored in the workbench and reinitialized if the plan is removed/replaced
If first time crafting and ticker = 0 set a flag to ignore ticker and craft as much as possible.