Analogous to ItemValueInput and StringValueInput, we need a QuantityValueInput componet.

• needs to adhere to the interface of ValueInput
  • take numberValue and unitValue props
  • emit input events for numberInput and unitInput and when the values change
  • take a disabled prop
  • take a error prop

• implement Lookup-behavior for unit lookup part
  • when the user types text into the unit lookup part of the query input -> search for item
  • present those items as menu items
  • if the user selects an item -> emit input event
  • react to scroll to load more results, etc.
  • => it needs to have all the functionality of EntityLookup and ItemValueLookup
    • consider synergies instead of duplicating that logic

open questions:

• the error prop will apply for now only to the number input. We still need to figure out when/how it should apply to the unit input