fix: after setting the cursor theme, it will not update in real-time.

[mhduiy]

Monitor the Gtk/CursorThemeName property and manually call changeCursor() to refresh the cursor when it changes

pms: BUG-296269

[deepin-ci-robot]

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This pull-request has been approved by: mhduiy

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[deepin-ci-robot]

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关键摘要:

• cursorThemePropertyChanged 函数中的 Q_UNUSED 宏用于忽略未使用的参数，但应该确保这些参数在未来的代码维护中不会被误用。
• QMetaObject::invokeMethod 使用了 Qt::QueuedConnection，这可能会导致界面响应延迟，应该评估是否需要立即更新。
• VtableHook::callOriginalFun 函数的调用可能存在潜在的线程安全问题，需要确保在调用时线程安全。
• xSettings()->registerCallbackForProperty 注册了一个回调函数，但没有提供回调函数的取消注册机制，可能会导致内存泄漏。

是否建议立即修改:
是