docs: update resources API docs

docs/api/resources/textureimportsettings/setnormalmapstrength.md

@@ -0,0 +1,27 @@
+# TextureImportSettings::SetNormalMapStrength / GetNormalMapStrength
+
+```cpp
+void SetNormalMapStrength(float strength);
+float GetNormalMapStrength() const;
+```
+
+设置或获取法线贴图强度。
+
+**参数：**
+- `strength` - 法线贴图强度系数
+
+**返回：** `float` / `void`
+
+**线程安全：** ✅
+
+**示例：**
+
+```cpp
+TextureImportSettings settings;
+settings.SetNormalMapStrength(2.0f);
+float strength = settings.GetNormalMapStrength(); // 2.0f
+```
+
+## 相关文档
+
+- [TextureImportSettings 总览](textureimportsettings.md) - 返回类总览