Merge a card refresh (#59)

- **Refactored Card Placement Flow**
  - Separated card presentation from orchestration logic
  - Extracted `CornerCardManager` for pending card lifecycle (spawn, shuffle, rebuild)
  - Extracted `AlbumNavigationService` for book page navigation and zone mapping
  - Extracted `CardEnlargeController` for backdrop management and card reparenting
  - Implemented controller pattern (non-MonoBehaviour) for complex logic
  - Cards now unparent from slots before rebuild to prevent premature destruction

- **Improved Corner Card Display**
  - Fixed cards spawning on top of each other during rebuild
  - Implemented shuffle-to-front logic (remaining cards occupy slots 0→1→2)
  - Added smart card selection (prioritizes cards matching current album page)
  - Pending cards now removed from queue immediately on drag start
  - Corner cards rebuild after each placement with proper slot reassignment

- **Enhanced Album Card Viewing**
  - Added dramatic scale increase when viewing cards from album slots
  - Implemented shrink animation when dismissing enlarged cards
  - Cards transition: `PlacedInSlotState` → `AlbumEnlargedState` → `PlacedInSlotState`
  - Backdrop shows/hides with card enlarge/shrink cycle
  - Cards reparent to enlarged container while viewing, return to slot after

- **State Machine Improvements**
  - Added `CardStateNames` constants for type-safe state transitions
  - Implemented `ICardClickHandler` and `ICardStateDragHandler` interfaces
  - State transitions now use cached property indices
  - `BoosterCardContext` separated from `CardContext` for single responsibility

- **Code Cleanup**
  - Identified unused `SlotContainerHelper.cs` (superseded by `CornerCardManager`)
  - Identified unused `BoosterPackDraggable.canOpenOnDrop` field
  - Identified unused `AlbumViewPage._previousInputMode` (hardcoded value)
  - Identified unused `Card.OnPlacedInAlbumSlot` event (no subscribers)

Co-authored-by: Michal Pikulski <michal.a.pikulski@gmail.com>
Co-authored-by: Michal Pikulski <michal@foolhardyhorizons.com>
Reviewed-on: #59

Assets/Scripts/CardSystem/StateMachine/CardStateNames.cs

@@ -0,0 +1,26 @@
+namespace UI.CardSystem.StateMachine
+{
+    /// <summary>
+    /// Centralized string constants for card state names.
+    /// Prevents typos and provides compile-time checking for state transitions.
+    /// </summary>
+    public static class CardStateNames
+    {
+        // Booster Flow States
+        public const string Idle = "IdleState";
+        public const string EnlargedNew = "EnlargedNewState";
+        public const string EnlargedRepeat = "EnlargedRepeatState";
+        public const string EnlargedLegendaryRepeat = "EnlargedLegendaryRepeatState";
+        public const string Revealed = "RevealedState";
+        
+        // Album Placement Flow States
+        public const string PendingFaceDown = "PendingFaceDownState";
+        public const string DraggingRevealed = "DraggingRevealedState";
+        public const string PlacedInSlot = "PlacedInSlotState";
+        public const string AlbumEnlarged = "AlbumEnlargedState";
+        
+        // Generic Drag State
+        public const string Dragging = "DraggingState";
+    }
+}
+