Grouped Print Queue

When you send multiple copies of the same part to the queue, they now collapse into a single row with a count badge — no more scrolling past the same thumbnail twenty times.

Each group row has:

• Adjust quantity — change the total copies between 1 and 500. Printago adds or removes copies in place.
• Split group — break a group into smaller groups (for example, split a group of 10 into a 3 + 7).
• Up/down arrows — reorder the whole group as one block.

Order-linked jobs keep their adjust action disabled since the order itself controls their lifecycle.