ARR: Improve SAC and AC matching processes

[haroldrubio]

SAC and AC assignments by paper purely maximizing affinity causes a lot of communication issues between SACs and ACs. The following proposed changes should allow SACs to be implicitly assigned ACs, taking into account track, while still using assignments to papers to enable the extra features supported by paper assignments:

1. (Optional if not provided) Infer SAC to a single track mapping by minimizing load variance and range
2. Run the AC matching and assign ACs to a single track by voting across their proposed assignment
3. Create groups of ACs in each track to balance the number of papers between groups of ACs, so the resulting SAC to group of ACs results in a balanced load within a track
4. Assign SACs to groups of ACs per track that minimizes conflicts
5. Using the SAC-AC mapping, run a second AC matching that transfers the SAC conflicts to their assigned ACs - so that their ACs avoid getting assignment papers that conflict with their assigned SAC
6. Deploy the AC matching and infer the SAC-paper assignments via the second AC matching