Add player controller, state management, and input handling

- Implemented PlayerController.cs to manage player movement and actions.
- Created PlayerState.cs to track player lives, coins, and key status.
- Added CameraFollow.cs for smooth camera movement following the player.
- Developed Character.cs as an abstract class for character behavior.
- Introduced Enums.cs for defining TreasureType and MapElementType.
- Added IDoor interface for door interactions.
- Created InputActions.cs for handling player input actions.
- Implemented MainMenu.cs for basic menu functionality including play and exit options.

Assets/Scripts/Utilities/CameraFollow.cs

@@ -0,0 +1,35 @@
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+public class CameraFollow : MonoBehaviour
+{
+    [SerializeField]
+    private Transform _followTarget;
+    [SerializeField]
+    private float _smoothTime = 0.15f;
+    [SerializeField]
+    private bool _stopAtXedges=false;
+    [SerializeField]
+    private float _maxXValue = 0f;
+    [SerializeField]
+    private float _minXValue = 0f;
+
+
+
+    Vector3 _velocity= Vector3.zero;
+
+    private void FixedUpdate()
+    {
+        var targetPosition=_followTarget.position;
+        targetPosition.z = transform.position.z;
+        targetPosition.y = transform.position.y;
+
+        if (_stopAtXedges)
+        {
+            targetPosition.x = Mathf.Clamp(targetPosition.x, _minXValue, _maxXValue);
+        }
+
+        transform.position = Vector3.SmoothDamp(transform.position, targetPosition, ref _velocity,_smoothTime);
+    }
+}