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/投射物和特效/ShieldBarrier.cs

@@ -0,0 +1,138 @@
+using UnityEngine;
+
+public class ShieldBarrier : MonoBehaviour
+{
+    [Header("盾牌状态")]
+    [Min(0f)]
+    public float maxDurability = 220f;
+
+    [Min(0f)]
+    public float currentDurability;
+
+    [Min(0f)]
+    public float duration = 6f;
+
+    [Range(-1f, 1f)]
+    public float frontDotThreshold = 0.15f;
+
+    private UnitBase owner;
+    private Collider barrierCollider;
+    private float remainingTime;
+
+    public UnitBase Owner => owner;
+
+    public float CurrentDurability => currentDurability;
+
+    public bool IsActive =>
+        isActiveAndEnabled &&
+        barrierCollider != null &&
+        barrierCollider.enabled &&
+        currentDurability > 0f &&
+        remainingTime > 0f;
+
+    public void Configure(UnitBase shieldOwner, Collider shieldCollider)
+    {
+        owner = shieldOwner;
+        barrierCollider = shieldCollider;
+    }
+
+    public void Refresh(float durability, float activeDuration, Vector3 localPosition, Vector3 localSize)
+    {
+        if (barrierCollider == null)
+        {
+            barrierCollider = GetComponent<Collider>();
+        }
+
+        if (owner == null)
+        {
+            owner = GetComponentInParent<UnitBase>();
+        }
+
+        transform.localPosition = localPosition;
+        transform.localRotation = Quaternion.identity;
+
+        BoxCollider boxCollider = barrierCollider as BoxCollider;
+        if (boxCollider != null)
+        {
+            boxCollider.center = Vector3.zero;
+            boxCollider.size = localSize;
+            boxCollider.isTrigger = true;
+        }
+
+        maxDurability = Mathf.Max(0.01f, durability);
+        currentDurability = maxDurability;
+        duration = Mathf.Max(0.01f, activeDuration);
+        remainingTime = duration;
+
+        gameObject.SetActive(true);
+        if (barrierCollider != null)
+        {
+            barrierCollider.enabled = true;
+        }
+    }
+
+    public bool TryBlock(GameObject attacker, float damage)
+    {
+        if (!IsActive || damage <= 0f)
+        {
+            return false;
+        }
+
+        if (attacker != null && !IsIncomingFromFront(attacker))
+        {
+            return false;
+        }
+
+        currentDurability -= damage;
+        if (currentDurability <= 0f)
+        {
+            DisableBarrier();
+        }
+
+        return true;
+    }
+
+    public void DisableBarrier()
+    {
+        currentDurability = 0f;
+        remainingTime = 0f;
+
+        if (barrierCollider != null)
+        {
+            barrierCollider.enabled = false;
+        }
+
+        gameObject.SetActive(false);
+    }
+
+    private void Update()
+    {
+        if (!IsActive)
+        {
+            return;
+        }
+
+        remainingTime -= Time.deltaTime;
+        if (remainingTime <= 0f)
+        {
+            DisableBarrier();
+        }
+    }
+
+    private bool IsIncomingFromFront(GameObject attacker)
+    {
+        if (owner == null)
+        {
+            return true;
+        }
+
+        Vector3 direction = attacker.transform.position - owner.transform.position;
+        direction.y = 0f;
+        if (direction.sqrMagnitude <= 0.0001f)
+        {
+            return true;
+        }
+
+        return Vector3.Dot(owner.transform.forward, direction.normalized) >= frontDotThreshold;
+    }
+}