bug: 同名文件无法覆盖

有如下文件夹结构：
```bash
E:.
├─A
│ test.rtf
│
└─B
test.rtf
```

其中文件夹 `A` 和文件夹 `B` 包含同名文件 `test.rtf`，现在将 `A` 中的 `test.rtf` 剪切后粘贴到 `B` 中，系统提示替换或跳过文件，选择“替换目标中的文件”，弹出“云操作不成功”的提示。

Start by reproducing the reported cut-and-paste overwrite operation between folders A and B in the desktop sync client, using same-named test.rtf files. Trace the handling of the replacement choice and the resulting “cloud operation unsuccessful” error. Done means replacing the destination file succeeds without that error.

Written by the indexing model from the issue text.