Fix/add row column plugin release error

[wkeylin]

[中文版模板 / Chinese template]

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🔗 Related issue link

fixed #5140

💡 Background and solution

AddRowColumnPlugin 的 release() 方法中直接调用了 this.leftDotForAddColumn.remove() 等 8 个 UI 元素的 remove() 方法。但这些 UI 元素（如 leftDotForAddColumn、rightDotForAddColumn、addIconForAddColumn 等）是在用户交互过程中懒创建的，如果插件在这些元素被创建之前就调用了 release()（例如初始化后直接销毁表格），这些属性为 undefined，导致抛出 Cannot read properties of undefined (reading 'remove') 错误。

在 release() 方法中对所有 UI 元素的 remove() 调用添加可选链操作符 ?.，确保元素未初始化时安全跳过，不会抛出异常

📝 Changelog

Language	Changelog
🇺🇸 English	fix: add optional chaining in AddRowColumnPlugin release to prevent errors
🇨🇳 Chinese	修复：AddRowColumnPlugin 的 release() 方法在 UI 元素未初始化时抛出空引用错误

☑️ Self-Check before Merge

⚠️ Please check all items below before requesting a reviewing. ⚠️

• Doc is updated/provided or not needed
• Demo is updated/provided or not needed
• TypeScript definition is updated/provided or not needed
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🚀 Summary

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🔍 Walkthrough

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