Stronger explanations

[Dekker1]

• Add ability to search for literals for stronger explanations
• Enable stronger explanation for DisjunctiveEdgeFinding

[codecov]

Codecov Report

Attention: Patch coverage is 60.26490% with 60 lines in your changes missing coverage. Please review.

Project coverage is 65.69%. Comparing base (e55a5d3) to head (549b30e).
Report is 1 commits behind head on develop.

Files	Patch %	Lines
crates/huub/src/solver/engine.rs	35.71%	27 Missing ⚠️
crates/huub/src/solver/engine/int_var.rs	55.17%	26 Missing ⚠️
crates/huub/src/actions/decision.rs	84.37%	5 Missing ⚠️
...ates/huub/src/solver/engine/propagation_context.rs	80.00%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop      #73      +/-   ##
===========================================
- Coverage    65.95%   65.69%   -0.26%     
===========================================
  Files           41       41              
  Lines         6335     6430      +95     
===========================================
+ Hits          4178     4224      +46     
- Misses        2157     2206      +49     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[codecov]

Welcome to Codecov 🎉

Once you merge this PR into your default branch, you're all set! Codecov will compare coverage reports and display results in all future pull requests.

ℹ️ You can also turn on project coverage checks and project coverage reporting on Pull Request comment

Thanks for integrating Codecov - We've got you covered ☂️