关于物料在引擎渲染时机的问题

## **Describe the bug (required)** / **详细描述 bug（必填）**

**场景**：组件A需要获取组件B的DOM元素，根据DOM元素位置信息做逻辑处理。
首先想到的方法是根据document.getElementById('组件B的id')获取，
但发现组件A渲染时无法知道画布中的组件B是否渲染，进而导致获取不到组件B的DOM

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## **Expected behavior (required)** / **预期行为（必填，非常重要）**
能够在组件A中准确获取到组件B的最新DOM元素信息.

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## **Screenshots (optional)** / **bug 截图（可选）**
伪代码：

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## **Environments (please complete the following information) (required):** / **请提供如下信息（必填）**
- AliLowCodeEngine version: [e.g. 1.0.0] / 低代码引擎版本
- AliLowCodeEngineExt version: [e.g. 1.0.0] / 低代码引擎扩展包版本
- Browser [e.g. chrome, safari] / 浏览器版本
- materials / plugins / tools / 其他物料 / 插件 / 工具链版本

> (this information can be collected via [the manual plugin](https://img.alicdn.com/imgextra/i1/O1CN0115zonY1IsgbkZ2ir7_!!6000000000949-2-tps-3066-1650.png) / 版本信息可[通过低代码用户手册插件收集](https://img.alicdn.com/imgextra/i1/O1CN0115zonY1IsgbkZ2ir7_!!6000000000949-2-tps-3066-1650.png))

## **Additional context (optional)** / **更多额外信息（可选）**
如果物料之间无法通信，如何在画布中组件A知道组件B渲染完毕了呢

Start by reproducing the canvas scenario with component A needing component B's DOM, and collect the missing engine, extension, browser, material, plugin, and tooling versions. The issue is done when A can reliably obtain B's latest DOM information or the supported cross-component communication and render-completion behavior is clearly established.

Written by the indexing model from the issue text.