car extract -f CID --> extract the CID always including folder, subfolder and files in the filesystem --> Retain the directory structure of the CID

When the CID is a directory which include files and folders and subfolders it is realy usefull when extracting the CID to filesystem with CLI command `car extract -f CID` it would keep the same directory structure and folders and subfolders are created in the filesystem.

When I download the CID with kubo or ipfs-desktop into a tar file, the folders and subfolders of the CID are also created.
This way it is possible to create the same CID again when uploading all to ipfs. This is very useful.

Please extract a CID wrapped in a directory always with folder (name of the CID) and files, folders and subfolders, …..

Start at the CLI entry point for `car extract -f CID` and trace how a directory CID is written to the filesystem. Compare the current behavior with the issue’s described Kubo or IPFS Desktop tar extraction, then verify that extraction preserves the CID directory, nested folders, and files so the content can be uploaded again with the same structure.

Written by the indexing model from the issue text.