452 fq childRes visible group cap wins

autotest-case: 452 scope: group freeQuantity; childRes=True group: fq.452 childRes visible group free 2 child free A B C group restrictions: min=3 max=3 free=2 children: prices=[30, 20, 10] defaults=[1, 1, 1] childMin=[1, 1, 1] childFree=[1, 1, 1] manual hide group: - manual hide child modifiers: [] expected: quick add chooses the most expensive eligible defaults as free; group free is the cap, and child free can additionally limit a child when childRes=true.