Every item on your packing list is always in one of three statuses — Need, Have, or Packed — and they mean the same thing everywhere: Edit items mode, Pack mode, or the shared list.
Need means you still have to get it or pack it. Have means you've got it but haven't packed it yet. Packed means it's done and ready to go. In Pack mode, each row is tinted by its status — need rows get a soft amber highlight — so you can scan a bag at a glance; Edit items mode keeps rows neutral since it's about building the list, not tracking pack-day progress.
In Pack mode, the filter bar above your list shows All / Need / Have / Packed, each with a live count. Underneath it, Group switches how the list is sectioned — by Bag, Status, or Type — and works independently of the status filter, so you can e.g. filter to Need while still grouped by Bag.