* [Refactor] Retype card containers and zone logic onto CardState
* [Game] Restore attach bookkeeping via CardItem and repaint on state change
* [Refactor] Give custom zones a hidden graphics owner
Custom PileZoneLogic zones had no CardZone, so moving a card into one
left the CardItem drawn at its old spot. Create a hidden PileZone in
onCustomZoneAdded so cards are reparented and hidden.
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Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>