feat(puffin): Add PuffinReader

[fqaiser94]

Part of #744

Summary

• Add PuffinReader

Context

• This is the fourth of a number of PRs to add support for Iceberg Puffin file format.
• It might be helpful to refer to the overarching PR from which these changes were split to understand better how these changes will fit in to the larger picture.
• It may also be helpful to refer to the Java reference implementation for PuffinReader here.

[liurenjie1024]

Thanks @fqaiser94 for this great pr, generally LGTM! Just some minor suggestions.

[liurenjie1024]

Should we consider using a LazyLock to initalize it? This way it could be thread safe, and discard the &mut modifier.

[fqaiser94]

I would love to be able to get rid of the &mut here 👍
Struggling to get a LazyLock based implementation working though.
The main challenge is that FileMetadata::read is an async function :/
Open to suggestions

[liurenjie1024]

I think async_lazy crate is a good fit?

[liurenjie1024]

Should we add comment to explain that this is always uncompressed data?

[waynexia]

Or can we include a CompressionCodec in the Blob to indicate the compress method? (we can do this in a follow-up PR)

[fqaiser94]

Should we add comment to explain that this is always uncompressed data?

Done.

Or can we include a CompressionCodec in the Blob to indicate the compress method? (we can do this in a follow-up PR)

I can see where you're coming from and while I'm not completely opposed to the idea, I think I prefer to return the uncompressed data at this point. I will also note that the Java PuffinReader API does the same i.e. always returns the data after decompression.