CAR support

[Ericson2314]

I am not sure whether this is in scope for this library, but asking anyway.

Would it possible to include something like what https://github.com/web3-storage/ipfs-car in this library? My understanding is that this is the proper way to securely work with a gateway:

1. Download CARs, not reassembled data (reassembly is per multiformat, but let's focus on DAG-PB since its flexibility in chunking is what creates the verification problem)
2. Verify CAR
3. Reassemble verified data

It is therefore nice to be able to do all the steps to support users with or without a full node without impaired security.

[Ericson2314]

FWIW it might be possible to convert ipfs-car from JS to python with aid of ChatGPT 😅.