fix: delete file on write failure and preserve parent directory

[nabil-Tounarti]

No description provided.

[Copilot]

Pull Request Overview

This PR improves the cleanup behavior in the download_file function by changing the error handling logic to only delete the failed file instead of removing the entire parent directory, preventing accidental deletion of existing directories when a file write fails.

Key changes:

• Modified cleanup logic to remove only the failed file instead of the parent directory when write operations fail
• Added error variable capture for better error logging
• Added comprehensive test coverage for the new cleanup behavior

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