fix(rhi): Fix RHI abstraction layer API docs per api-skill.md template

- Rename texture/dtor.md to destructor.md per template spec
- Remove duplicate non-hyphenated fence docs (getnativehandle.md, issignaled.md, getcompletedvalue.md)
- Fix template field issues:
  - swap-chain, command-queue: 类型 now uses 'class (abstract)'
  - sampler: 头文件 now uses full path 'XCEngine/RHI/RHISampler.h'
  - types: 类型 fixed from 'structs' to 'struct'
  - enums: 类型 fixed from 'enums' to 'enum class'
- Fix include paths in command-queue and pipeline-layout code examples
- Create missing constructor/destructor docs for 11 classes:
  buffer, texture, shader, device, command-list, command-queue,
  fence, sampler, swap-chain, pipeline-state, pipeline-layout
- Update class overview pages to include constructor/destructor entries

docs/api/rhi/fence/constructor.md

@@ -0,0 +1,28 @@
+# RHIFence::RHIFence
+
+```cpp
+RHIFence() = default;
+```
+
+默认构造函数，创建空的 RHIFence 对象。
+
+**参数：** 无
+
+**返回：** 无
+
+**线程安全：** ✅
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+// 通过设备创建围栏
+RHIFence* fence = device->CreateFence(desc);
+// fence 现在是一个有效的围栏引用
+```
+
+## 相关文档
+
+- [RHIFence 总览](fence.md) - 返回类总览
+- [CreateFence](../device/create-fence.md) - 创建围栏