fix: dde-file-manager crash, search crash

[liyigang1]

if window not exists, don't send sendStopSpinner event

Log: dde-file-manager crash, search crash
Bug: https://pms.uniontech.com/task-view-358757.html

[deepin-ci-robot]

deepin pr auto review

关键摘要:

• 在CrumbInterface::onUpdateChildren方法中，直接使用child.fileName()替换了info->nameOf(NameInfoType::kFileName)，可能会导致文件名编码问题。建议检查child.fileName()的实现是否能够正确处理不同编码的文件名。
• 在SearchEventCaller::sendStopSpinner方法中，增加了对窗口ID的检查，以确保发送的信号仅针对存在的窗口。这是一个好的做法，可以避免潜在的崩溃问题。

是否建议立即修改:

• 是，建议立即修改CrumbInterface::onUpdateChildren方法中的文件名编码问题，以确保代码的健壮性和跨平台兼容性。
• 是，建议立即修改SearchEventCaller::sendStopSpinner方法中的窗口检查逻辑，以确保代码的健壮性和性能。

[deepin-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: liyigang1, max-lvs

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