fix(image-viewer): update trigger prop to accept index parameter

[betavs]

🤔 这个 PR 的性质是？

• 日常 bug 修复
• 新特性提交
• 文档改进
• 演示代码改进
• 组件样式/交互改进
• CI/CD 改进
• 重构
• 代码风格优化
• 测试用例
• 分支合并
• 其他

🔗 相关 Issue

from TDesignOteam/tdesign-api#686

💡 需求背景和解决方案

📝 更新日志

• feat(ImageViewer): 支持 trigger 传入图片 index 参数，trigger 的 open 方法参数可能与绑定的元素触发事件存在类型差异情况，若遇到此问题请改成 ()=> open() 类似匿名函数使用

• 本条 PR 不需要纳入 Changelog

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⚠️ 请自检并全部勾选全部选项。⚠️

• 文档已补充或无须补充
• 代码演示已提供或无须提供
• TypeScript 定义已补充或无须补充
• Changelog 已提供或无须提供

[github-actions]

[pkg-pr-new]

tdesign-react-demo

npm i https://pkg.pr.new/tdesign-react@3827

commit: bab27f1

[Copilot]

Pull Request Overview

This PR updates the ImageViewer component's trigger prop to accept an optional index parameter in the open function, allowing developers to specify which image should be displayed when opening the viewer.

• Updates the trigger prop type definition to accept (index?: number) => void for the open function
• Removes defaultIndex prop usage in examples and uses the new index parameter instead
• Updates all example components and tests to use arrow functions when calling open()

Reviewed Changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
type.ts	Updates trigger prop type to accept optional index parameter
image-viewer.md	Updates documentation for new trigger type signature
image-viewer.en-US.md	Updates English documentation for new trigger type signature
ImageViewer.tsx	Implements index parameter handling in open function and uses useIndex hook
ImageViewerModal.tsx	Updates index change handling and adds 'current' trigger context
_example/*.tsx	Updates all examples to use arrow functions and index parameter
tests/image-viewer.test.tsx	Updates test cases to use arrow functions for open calls
upload/themes/DraggerFile.tsx	Updates to use arrow function for open call

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