增加支持在ResultMap中使用连续属性访问对结果集对象中的嵌套属性赋值;

[nbut-xzy]

功能改进 / Feature Enhancements

1. 新增核心接口与实现 / Added Core Interface and Implementations

   • 添加 IPropertyHolder 接口，统一属性访问逻辑
     Added IPropertyHolder interface to unify property access logic
   • 修改 PropertyHolder 类继承自 IPropertyHolder
     Modified PropertyHolder to inherit from IPropertyHolder
   • 新增 PropertyChainHolder 类实现嵌套属性链支持
     Added PropertyChainHolder class to support nested property chains

2. 嵌套属性映射支持 / Nested Property Mapping Support

   • 修改 EntityDeserializer.ResolveProperty 方法，支持解析如 NestedProp1.NestedProp2 的连续属性路径
     Modified EntityDeserializer.ResolveProperty to resolve chained property paths (e.g., NestedProp1.NestedProp2)
   • 修改 EntityDeserializer.CreateDeserialize 方法，自动初始化空嵌套对象
     Modified EntityDeserializer.CreateDeserialize to auto-initialize null nested objects
   • 支持如下 ResultMap 配置 / Supports ResultMap configuration like:

     <ResultMaps>
       <ResultMap Id="NestedPropertyResultMap">
         <Result Column="Id" Property="Id"/>
         <Result Column="String" Property="NestedProp1.NestedProp2.NestedProp3"/>
       </ResultMap>
     </ResultMaps>

3. 测试覆盖 / Testing

   • 新增嵌套属性映射单元测试
     Added unit tests for nested property mapping
   • 验证多层级对象初始化与数据完整性
     Validated multi-level object initialization and data integrity

---

影响范围 / Impact

• 文件修改 / Modified Files:
  IPropertyHolder.cs, PropertyHolder.cs, PropertyChainHolder.cs, EntityDeserializer.cs
• 测试新增 / Added Tests:
  EntityDeserializerTest.cs, AllPrimitive.xml, NestedEntity.cs

---

示例场景 / Example Usage

// 查询并映射嵌套属性 / Query with nested property mapping
var list = SqlMapper.Query<NestedEntity>(new RequestContext
{
    Scope = nameof(AllPrimitive),
    SqlId = "QueryNestedPropertyResult", // SQL statement ID (SQL语句ID)
    Request = new { Taken = 10000 }      // Query parameters (查询参数)
});

<ResultMaps>
 <ResultMap Id="NestedPropertyResultMap">
   <Result Column="Id" Property="Id"/>
   <Result Column="String" Property="NestedProp1.NestedProp2.NestedProp3"/>
 </ResultMap>
</ResultMaps>

public class NestedEntity
{
    public virtual long Id { get; set; }
    public virtual NestedProperty1 NestedProp1 { get; set; }
}
public class NestedProperty1
{
    public virtual NestedProperty2 NestedProp2 { get; set; }
}
public class NestedProperty2
{
    public virtual string NestedProp3 { get; set; }
}

[nbut-xzy]

代码文件的字符编码从GBK修正为UTF-8；

[nbut-xzy]

review changes

[xiangxiren]

注释乱码。同时，建议去掉里面的中英文混合注释，还有类似这样的示例注释（例如 User.Address.City）

[xiangxiren]

Property为何不直接定义为只读。PropertyInfo Property { get; }

[xiangxiren]

注释太多了（中英文混合）

[xiangxiren]

建议 PropertyInfo Property { get; }