feat(air): migrate range checker bus to LogUp

[grjte]

This PR addresses #982 and #299 (no longer needed), simplifying the range checker to require only 2 main trace columns and a single auxiliary trace column.

• rewrite AIR constraints
• rewrite trace generation of main range checker trace
• rewrite auxiliary trace generation for range checker lookup bus
• update tests

[grjte]

Notes:

• the docs need a really big update, so I think I should tackle it in a separate PR
• Currently we pad the range checker at the beginning of the trace. I think we could now pad at the end with rows of u16::MAX of multiplicity 0, and this would simplify things. Wdyt? I left it as is for now, to reduce the amount of changes.

[bobbinth]

Looks great! Thank you! I left a few small blocking comments inline - some of them can be left for future PRs.

Re moving padding to the end - yes, let's leave it for a future PR. We can also combine this with one other potential optimization idea i left inline.

[bobbinth]

Oh - one other thing: let's update the changelog to include this change.