add special handling for pseudo-boolean constraints

[AllenZzw]

Add special handling for two pseudo-boolean constraints:

• $b_i + b_j \leq 1 === (\neg b_i) \vee (\neg b_j)$
• $\sum_i b_i \geq 1 === \vee_i b_i$

[codecov]

Codecov Report

Attention: Patch coverage is 52.38095% with 10 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
crates/huub/src/constraints/int_linear.rs	52.38%	9 Missing and 1 partial ⚠️

Files with missing lines	Coverage Δ
crates/huub/src/constraints/int_linear.rs	86.19% <52.38%> (-1.12%)	⬇️

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[codspeed-hq]

CodSpeed Performance Report

Merging #162 will degrade performances by 8.24%

_{Comparing AllenZzw:feat/special_linear (038212e) with develop (906daee)}

Summary

❌ 1 regressions
✅ 13 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
❌	satisfaction[amaze3_2012_03_19]	705.9 ms	769.4 ms	-8.24%

[Dekker1]

I think the idea of special handling is a good idea, but I'm not sure about this implementation. Didn't we talk about using the BoolLinAggregator from pindakaas?

I'll see if I can whip up an implementation so you can try and see if it also solves your case.

The main thing would be that it further simplifies the constraints and also allows use to further distinguish the different linear variants if we want to do something with it in the future.

[AllenZzw]

Yes, we should definitely try BoolLinAggregator. Just added two most common and useful cases here. We can try to switch to BoolLinAggregator once we have the interface.

[AllenZzw]

Close as this is handled in #163