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/FormationCardDrag.cs

@@ -0,0 +1,96 @@
+using UnityEngine;
+using UnityEngine.EventSystems;
+using UnityEngine.UI;
+
+/// <summary>
+/// 底部英雄卡片的拖拽：拖到网格格位上放置英雄。
+/// 吸附与放置由 FormationManager 负责，卡片只负责拖动表现和回调。
+/// </summary>
+[RequireComponent(typeof(CanvasGroup))]
+public class FormationCardDrag : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
+{
+    [Header("界面引用")]
+    public Image background;
+    public Image icon;
+    public Text nameText;
+
+    [HideInInspector] public FormationManager manager;
+    [HideInInspector] public int heroIndex;
+
+    private RectTransform rectTransform;
+    private CanvasGroup canvasGroup;
+    private Vector2 homePosition;
+
+    private static readonly Color NormalColor = new Color(0.15f, 0.15f, 0.2f, 0.92f);
+    private static readonly Color PlacedColor = new Color(0.18f, 0.18f, 0.22f, 0.45f);
+
+    private void Awake()
+    {
+        rectTransform = GetComponent<RectTransform>();
+        canvasGroup = GetComponent<CanvasGroup>();
+        homePosition = rectTransform.anchoredPosition;
+    }
+
+    /// <summary>填入名字与头像。</summary>
+    public void SetContent(string displayName, Sprite iconSprite)
+    {
+        if (nameText != null) nameText.text = displayName;
+        if (icon != null)
+        {
+            if (iconSprite != null)
+            {
+                icon.sprite = iconSprite;
+                icon.preserveAspect = true;
+                icon.color = Color.white;
+            }
+            else
+            {
+                icon.color = new Color(0.4f, 0.4f, 0.45f, 1f);
+            }
+        }
+    }
+
+    /// <summary>已放置的卡片置灰并禁止再次拖拽。</summary>
+    public void SetPlaced(bool isPlaced)
+    {
+        if (background != null) background.color = isPlaced ? PlacedColor : NormalColor;
+        canvasGroup.alpha = isPlaced ? 0.55f : 1f;
+    }
+
+    public void OnBeginDrag(PointerEventData eventData)
+    {
+        if (manager == null || !manager.CanDrag(heroIndex))
+        {
+            return;
+        }
+
+        canvasGroup.blocksRaycasts = false;
+        rectTransform.position = eventData.position;
+        manager.OnCardDragStart(heroIndex);
+    }
+
+    public void OnDrag(PointerEventData eventData)
+    {
+        if (manager == null || !manager.CanDrag(heroIndex))
+        {
+            return;
+        }
+
+        rectTransform.position = eventData.position;
+        manager.OnCardDragging(heroIndex, eventData.position);
+    }
+
+    public void OnEndDrag(PointerEventData eventData)
+    {
+        canvasGroup.blocksRaycasts = true;
+
+        if (manager == null || !manager.CanDrag(heroIndex))
+        {
+            rectTransform.anchoredPosition = homePosition;
+            return;
+        }
+
+        rectTransform.anchoredPosition = homePosition;
+        manager.OnCardDragEnd(heroIndex, eventData.position);
+    }
+}