Add multiplicity tracking for lookups

[mrmr1993]

This PR builds upon #2950. This PR adds tracking for fixed-table multiplicities in the witness generation. We can use these to inject them at the end of execution, for use in the lookup protocol. This way, we can use the delayed lookup argument for everything.

The indexing code is bad; this is mostly derived from existing code.

[codecov]

Codecov Report

Attention: Patch coverage is 65.95745% with 16 lines in your changes missing coverage. Please review.

Project coverage is 76.60%. Comparing base (2136d6c) to head (3796eb9).
Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
o1vm/src/interpreters/mips/witness.rs	64.51%	11 Missing ⚠️
o1vm/src/lookups.rs	66.66%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2943      +/-   ##
==========================================
- Coverage   76.61%   76.60%   -0.01%     
==========================================
  Files         255      255              
  Lines       60855    60897      +42     
==========================================
+ Hits        46622    46650      +28     
- Misses      14233    14247      +14     

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