Refactoring of the interaction system and preliminary integration of save/load functionality across the game. (#44)

### Interactables Architecture Refactor
- Converted composition to inheritance, moved from component-based to class-based interactables. No more requirement for chain of "Interactable -> Item" etc.
- Created `InteractableBase` abstract base class with common functionality that replaces the old component
- Specialized child classes: `Pickup`, `ItemSlot`, `LevelSwitch`, `MinigameSwitch`, `CombinationItem`, `OneClickInteraction` are now children classes
- Light updates to the interactable inspector, moved some things arround, added collapsible inspector sections in the  UI for better editor experience

### State Machine Integration
- Custom `AppleMachine` inheritong from Pixelplacement's StateMachine which implements our own interface for saving, easy place for future improvements
- Replaced all previous StateMachines by `AppleMachine`
- Custom `AppleState`  extends from default `State`. Added serialization, split state logic into "EnterState", "RestoreState", "ExitState" allowing for separate logic when triggering in-game vs loading game
- Restores directly to target state without triggering transitional logic
- Migration tool converts existing instances

### Prefab Organization
- Saved changes from scenes into prefabs
- Cleaned up duplicated components, confusing prefabs hierarchies
- Created prefab variants where possible
- Consolidated Environment prefabs and moved them out of Placeholders subfolder into main Environment folder
- Organized item prefabs from PrefabsPLACEHOLDER into proper Items folder
- Updated prefab references - All scene references updated to new locations
- Removed placeholder files from Characters, Levels, UI, and Minigames folders

### Scene Updates
- Quarry scene with major updates
- Saved multiple working versions (Quarry, Quarry_Fixed, Quarry_OLD)
- Added proper lighting data
- Updated all interactable components to new architecture

### Minor editor tools
- New tool for testing cards from an editor window (no in-scene object required)
- Updated Interactable Inspector
- New debug option to opt in-and-out of the save/load system
- Tooling for easier migration

Co-authored-by: Michal Pikulski <michal.a.pikulski@gmail.com>
Reviewed-on: #44

Assets/Scripts/Input/PlayerTouchController.cs

@@ -2,14 +2,26 @@
 using Pathfinding;
 using AppleHills.Core.Settings;
 using Core;
+using Core.SaveLoad;
+using Bootstrap;
 
 namespace Input
 {
+    /// <summary>
+    /// Saveable data for PlayerTouchController state
+    /// </summary>
+    [System.Serializable]
+    public class PlayerSaveData
+    {
+        public Vector3 worldPosition;
+        public Quaternion worldRotation;
+    }
+
     /// <summary>
     /// Handles player movement in response to tap and hold input events.
     /// Supports both direct and pathfinding movement modes, and provides event/callbacks for arrival/cancellation.
     /// </summary>
-    public class PlayerTouchController : MonoBehaviour, ITouchInputConsumer
+    public class PlayerTouchController : MonoBehaviour, ITouchInputConsumer, ISaveParticipant
     {
         // --- Movement State ---
         private Vector3 targetPosition;
@@ -55,6 +67,9 @@ namespace Input
         private bool interruptMoveTo;
         private LogVerbosity _logVerbosity = LogVerbosity.Warning;
 
+        // Save system tracking
+        private bool hasBeenRestored;
+
         void Awake()
         {
             aiPath = GetComponent<AIPath>();
@@ -71,6 +86,9 @@ namespace Input
 
             // Initialize settings reference using GetSettingsObject
             _settings = GameManager.GetSettingsObject<IPlayerFollowerSettings>();
+            
+            // Register for post-boot initialization
+            BootCompletionService.RegisterInitAction(InitializePostBoot);
         }
 
         void Start()
@@ -79,6 +97,29 @@ namespace Input
             _logVerbosity = DeveloperSettingsProvider.Instance.GetSettings<DebugSettings>().inputLogVerbosity;
         }
 
+        private void InitializePostBoot()
+        {
+            // Register with save system after boot
+            if (SaveLoadManager.Instance != null)
+            {
+                SaveLoadManager.Instance.RegisterParticipant(this);
+                Logging.Debug("[PlayerTouchController] Registered with SaveLoadManager");
+            }
+            else
+            {
+                Logging.Warning("[PlayerTouchController] SaveLoadManager not available for registration");
+            }
+        }
+
+        void OnDestroy()
+        {
+            // Unregister from save system
+            if (SaveLoadManager.Instance != null)
+            {
+                SaveLoadManager.Instance.UnregisterParticipant(GetSaveId());
+            }
+        }
+
         /// <summary>
         /// Handles tap input. Always uses pathfinding to move to the tapped location.
         /// Cancels any in-progress MoveToAndNotify.
@@ -415,5 +456,52 @@ namespace Input
                 Logging.Debug($"[PlayerTouchController] {message}");
             }
         }
+
+        #region ISaveParticipant Implementation
+
+        public bool HasBeenRestored => hasBeenRestored;
+
+        public string GetSaveId()
+        {
+            return "PlayerController";
+        }
+
+        public string SerializeState()
+        {
+            var saveData = new PlayerSaveData
+            {
+                worldPosition = transform.position,
+                worldRotation = transform.rotation
+            };
+            return JsonUtility.ToJson(saveData);
+        }
+
+        public void RestoreState(string serializedData)
+        {
+            if (string.IsNullOrEmpty(serializedData))
+            {
+                Logging.Debug("[PlayerTouchController] No saved state to restore");
+                hasBeenRestored = true;
+                return;
+            }
+
+            try
+            {
+                var saveData = JsonUtility.FromJson<PlayerSaveData>(serializedData);
+                if (saveData != null)
+                {
+                    transform.position = saveData.worldPosition;
+                    transform.rotation = saveData.worldRotation;
+                    hasBeenRestored = true;
+                    Logging.Debug($"[PlayerTouchController] Restored position: {saveData.worldPosition}");
+                }
+            }
+            catch (System.Exception ex)
+            {
+                Logging.Warning($"[PlayerTouchController] Failed to restore state: {ex.Message}");
+            }
+        }
+
+        #endregion
     }
 }