Use boxes & refs in Rust bindings

[jtraglia]

This PR fixes the issue with Windows & should be overall more efficient.

• When dealing with individual blobs, box them (store them on the heap).
  • This fixes the segmentation fault crash on Windows on 4844-devnet-7.
  • My theory is that these (relatively large) blobs were overflowing the stack.
• For all of the KZG interface functions, take references.
  • I feel like this should have done this a while ago.
  • It should be more efficient as it saves us from cloning.

Note, this does not fix the benchmark issue on Windows:

• Broken CI in rust-windows because of rust-1.7.0 #318

[jtraglia]

Actually, dang. Hold off on reviewing this. This PR still has the Windows segfault issue on 4844-devnet-7. I'll need to look into why the "boxed-blobs" branch works and this one doesn't.

[jtraglia]

Still unable to get this working. Will re-open if something changes.