fix: #948 下拉菜单点击穿透到预览视窗拉条

[Saraph1nes]

[tencent-adm]

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[github-actions[bot]]

【预览链接】

• full model
• basic
• mobile
• multiple instances
• editor without toolbar
• pure preview
• XSS（Not allowed by default）
• img wysiwyg
• table wysiwyg
• headers with auto num
• 流式输入模式（AI chart场景）
• VIM 编辑模式