Aggregate implications

[fwesselm]

Description

This PR adds aggregations for implied bounds (implications) as described by Chen et al., Exploiting Variable Implications in Presolve for Mixed Integer Programming.

Note that the current code does not consider cliques, i.e. "implications" between binary variables.

Unfortunately, the effect on performance is relatively small (ratios of shifted geometric means are close to 1.0). However, the models gfd-schedulen180f7d50m30k18 and neos-4763324-toguru (where 50% of the rows are eliminated) can be solved to optimality within a time limit of two hours with the new technique.

I added unit tests for the new technique.

Note that the paper also describes "implication aware" constraint propagation, which I will investigate next.

Checklist

• I have read the contributing guidelines
• This PR targets the latest branch
• Tests are passing
• Documentation was updated where relevant
• This PR is not primarily AI-generated (per the AI contributions policy in CONTRIBUTING.md)

[codecov]

Codecov Report

❌ Patch coverage is 96.41944% with 14 lines in your changes missing coverage. Please review.
✅ Project coverage is 73.43%. Comparing base (a2b94fa) to head (b5f97b2).
⚠️ Report is 36 commits behind head on latest.

Files with missing lines	Patch %	Lines
highs/mip/HighsCliqueTable.cpp	79.59%	10 Missing ⚠️
check/TestPresolveRules.cpp	98.46%	2 Missing ⚠️
highs/presolve/HPresolve.cpp	98.44%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           latest    #3264      +/-   ##
==========================================
+ Coverage   73.29%   73.43%   +0.13%     
==========================================
  Files         446      446              
  Lines      108244   108549     +305     
  Branches    17352    17395      +43     
==========================================
+ Hits        79342    79711     +369     
+ Misses      28626    28562      -64     
  Partials      276      276              

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[Opt-Mucca]

@fwesselm I've got one C++ question and one potential correctness error that I believe is a one line fix. The rest looks good!

[Opt-Mucca]

@fwesselm I'm happy for this to be merged whenever now provided that it's performance positive