feat(components): [skeleton] throttle supports values ​​as object (#17041)

* fix(components): [skeleton] `throttle` property not working

* fix: lint fix

* feat: add func & doc & test

* feat: remove test modify

* feat: increase document examples, improve document descriptions

* fix(components): [skeleton] `throttle` property not working

* fix: lint fix

* feat: add func & doc & test

* feat: remove test modify

* feat: increase document examples, improve document descriptions

* feat: 重构`useThrottleRender`钩子以提高代码可读性和效率

- 简化了对`throttle`参数的判断逻辑，通过`isNumber`函数判断是否为数字
- 将`leadingDispatch`和`trailingDispatch`函数合并为`dispatcher`函数，根据传入的类型判断执行逻辑
- 优化了`watch`回调函数，使用`dispatcher`函数替代重复的判断逻辑

* feat: 写法优化

* feat: 引入`isObject`函数替代原有的`typeof throttle === 'object'`判断方式

* feat: 优化骨架屏文档结构和示例

* feat: 完善文字描述和修改对应的文件名

* Update docs/en-US/component/skeleton.md

Co-authored-by: btea <2356281422@qq.com>

* Update docs/en-US/component/skeleton.md

Co-authored-by: btea <2356281422@qq.com>

* feat: Optimize code writing

* Update docs/en-US/component/skeleton.md

Co-authored-by: btea <2356281422@qq.com>

* Update docs/en-US/component/skeleton.md

* feat: modify doc

* feat: md

* feat: 补充 useThrottleRender 钩子的测试用例

* feat: 将 SkeletonThrottle 类型移动到hook中， 重命名为 ThrottleType 以提高通用性

---------

Co-authored-by: btea <2356281422@qq.com>

docs/examples/skeleton/avoiding-rendering-bouncing.vue

@@ -11,7 +11,7 @@
       :throttle="500"
     >
       <template #template>
-        <el-skeleton-item variant="image" style="width: 240px; height: 240px" />
+        <el-skeleton-item variant="image" style="width: 240px; height: 265px" />
         <div style="padding: 14px">
           <el-skeleton-item variant="h3" style="width: 50%" />
           <div