feat: on-demand rendering

[nini22P]

实现按需渲染，以减少静止状态下的性能消耗

[gemini-code-assist]

Summary of Changes

Hello @nini22P, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

此拉取请求引入了 PixiJS 的按需渲染机制，旨在显著降低舞台在静止状态下的性能消耗。通过动态控制 PixiJS 的渲染循环（ticker），当没有动画或动态元素时停止渲染，并在静态内容发生变化时手动触发渲染，从而实现了这一目标。

Highlights

• 引入按需渲染机制: PIXI.Application 默认 autoStart: false，并新增 requestRender 方法，用于在需要时手动触发渲染。
• 动态控制渲染循环: 新增 updateTickerStatus 方法，根据舞台上是否存在动画、Live2D、Spine、动态背景（视频/GIF）或GIF立绘等动态元素，自动启动或停止 PixiJS 的渲染循环（ticker）。
• 响应式列表管理: figureObjects、backgroundObjects 和 stageAnimations 现在通过 createReactiveList 方法创建，该方法使用 Proxy 监听列表变化，并在变化时自动调用 updateTickerStatus 以更新渲染状态。
• 优化静态场景性能: 当舞台处于静止状态（无动态元素）时，渲染循环将停止，显著减少CPU和GPU的资源消耗。
• 确保UI更新: 在纹理更新、背景/立绘添加以及从回溯日志恢复性能后，会调用 requestRender 确保画面及时刷新。

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[gemini-code-assist]

Code Review

本次 PR 实现了按需渲染，通过在 PIXI 应用中设置 autoStart: false 并在必要时手动调用渲染或启停 ticker，有效减少了应用在静止状态下的性能消耗。整体实现思路清晰，通过 Proxy 实现响应式数组来自动管理 ticker 状态是很好的实践。

我提出了一些可以改进的地方：

1. 简化 createReactiveList 中冗余的 if/else 判断。
2. 简化 requestRender 中的异步调用，使其更清晰。
3. 重构 updateTickerStatus 中的条件判断逻辑，提高代码可读性。

这些修改将有助于提升代码质量和可维护性。