Optimize construction of multi-linear polynomials for final sum-check

[Al-Kindi-0]

Before running the final sum-check of GKR in LogUp-GKR, we need to build multi-linear extensions of the relevant main trace columns. These are originally over the base field but the multi-linear extension as it is currently constructed stores them as extension field elements.
We should investigate if it is possible to avoid this as it could provide a nice reduction in the memory footprint.