[WIP] Fix renameDir function to support Windows

[Copilot]

Fix renameDir function for Windows

Issue Analysis

The renameDir function in backup_windows.go is trying to handle directories as files:

• Uses os.Open() and os.Create() which are for files, not directories
• Uses io.Copy() which copies file contents, not directory trees
• This will fail when trying to rename/move directories containing files

Plan

• Explore repository and identify the issue
• Understand how renameDir is used in the codebase
• Implement proper recursive directory copy for Windows
• Add tests to validate the fix
• Run tests to ensure the fix works
• Request code review
• Run security checks

Original prompt

can you review the function renameDir to make it work on windows?

Created from VS Code via the GitHub Pull Request extension.

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