function handleInput(e: KeyboardEvent) {
    if (e.key === 'Enter') {
      dispatch('enter');
      return;
    }
  }

Error: Type '(e: KeyboardEvent) => void' is not assignable to type 'EventHandler<Event, HTMLInputElement>'.
  Types of parameters 'e' and 'event' are incompatible.
    Type 'Event & { currentTarget: EventTarget & HTMLInputElement; }' is missing the following properties from type 'KeyboardEvent': altKey, char, charCode, code, and 16 more. (ts)
      on:keyup={handleInput}
      on:change={handleInput}
      bind:value={p.quantity}

const handleInput: EventHandler<KeyboardEvent, HTMLInputElement>(e) => {
    if (e.key === 'Enter') {
      dispatch('enter');
      return;
    }
  }