根据提供的code differences信息，由于没有具体的代码变更内容，我将生成一个通用的commit message模板：

```
docs(readme): 更新文档说明

- 添加项目使用指南
- 完善API接口说明
- 修正错误的配置示例
```

注意：由于您提供的code differences部分为空，以上是一个示例模板。当您有具体的代码变更时，请提供详细的变更内容以便生成更准确的commit message。

Assets/Scripts/UI脚本/DeployHighlight.cs

@@ -0,0 +1,113 @@
+using UnityEngine;
+
+/// <summary>
+/// 部署格位高亮：拖动卡牌时在目标格位显示一块发光地板。
+/// 绿色 = 可以放置；红色 = 该格已被占用 / 不可放置。
+/// 全场只需要一个，由 DefenseGameFlowController 在布阵阶段创建。
+/// </summary>
+public class DeployHighlight : MonoBehaviour
+{
+    public static DeployHighlight Instance { get; private set; }
+
+    private static readonly Color FreeColor = new Color(0.25f, 1f, 0.45f, 0.55f);
+    private static readonly Color BlockedColor = new Color(1f, 0.28f, 0.28f, 0.55f);
+
+    private GameObject plate;
+    private Material plateMaterial;
+    private int shownCell = -1;
+
+    /// <summary>高亮当前是否可见。</summary>
+    public bool IsVisible => plate != null && plate.activeSelf;
+
+    /// <summary>当前显示的是否是"不可放置"（红色）。</summary>
+    public bool IsBlocked { get; private set; }
+
+    /// <summary>当前高亮所在的格位，-1 表示没有。</summary>
+    public int ShownCell => shownCell;
+
+    public static DeployHighlight Ensure()
+    {
+        if (Instance != null) return Instance;
+
+        var go = new GameObject("DeployHighlight");
+        Instance = go.AddComponent<DeployHighlight>();
+        Instance.Build();
+        return Instance;
+    }
+
+    private void Awake()
+    {
+        if (Instance == null)
+        {
+            Instance = this;
+            Build();
+        }
+    }
+
+    private void Build()
+    {
+        if (plate != null) return;
+
+        plate = GameObject.CreatePrimitive(PrimitiveType.Cube);
+        plate.name = "CellPlate";
+        plate.transform.SetParent(transform, false);
+        plate.transform.localRotation = Quaternion.identity;
+        plate.transform.localScale = new Vector3(DeployGrid.CellWidth * 0.96f, 0.02f, DeployGrid.CellDepth * 0.96f);
+
+        // 高亮只是视觉提示，不需要碰撞
+        var collider = plate.GetComponent<Collider>();
+        if (collider != null)
+        {
+            Destroy(collider);
+        }
+
+        var shader = Shader.Find("Sprites/Default") ?? Shader.Find("Unlit/Color");
+        plateMaterial = new Material(shader);
+        plateMaterial.name = "DeployHighlightMat";
+        plateMaterial.color = FreeColor;
+
+        var renderer = plate.GetComponent<Renderer>();
+        renderer.sharedMaterial = plateMaterial;
+        renderer.shadowCastingMode = UnityEngine.Rendering.ShadowCastingMode.Off;
+        renderer.receiveShadows = false;
+
+        plate.SetActive(false);
+    }
+
+    /// <summary>在指定格位显示高亮。blocked = true 显示红色。</summary>
+    public void Show(int cellIndex, bool blocked)
+    {
+        if (plate == null) Build();
+        if (!DeployGrid.IsValidIndex(cellIndex))
+        {
+            Hide();
+            return;
+        }
+
+        var pos = DeployGrid.CellPosition(cellIndex);
+        plate.transform.position = new Vector3(pos.x, DeployGrid.GridY + 0.05f, pos.z);
+        plateMaterial.color = blocked ? BlockedColor : FreeColor;
+        IsBlocked = blocked;
+
+        if (shownCell != cellIndex || !plate.activeSelf)
+        {
+            plate.SetActive(true);
+            shownCell = cellIndex;
+        }
+    }
+
+    public void Hide()
+    {
+        if (plate != null && plate.activeSelf)
+        {
+            plate.SetActive(false);
+        }
+        shownCell = -1;
+        IsBlocked = false;
+    }
+
+    private void OnDestroy()
+    {
+        if (Instance == this) Instance = null;
+    }
+}