Expand and test LevelDemand functionality

[SouthEndMusic]

Fixes #2319.
Fixes #2418.

[SouthEndMusic]

I updated the Julia Tests workflow so that now when allocation fails, the failing problem together with analysis data is written as an artifact that can be downloaded from Github 👍

[SouthEndMusic]

@visr I can't get the Heisenbug model to fail. Given that we get useful artifacts when it does fail, are you fine with keeping these tests active?

Edit: it failed on windows 🙏

[jarsarasty]

Hi @SouthEndMusic

The problem is actually feasible when solving it with CPLEX. This is the log from the NEOS server:

MIP - Integer optimal solution:  Objective =  0.0000000000e+00
Solution time =    0.01 sec.  Iterations = 46  Nodes = 0
Deterministic time = 1.93 ticks  (176.04 ticks/sec)

So the issue is happening in the HiGHS solver. We should create a minimal reproducible example to report the issue to the HiGHS developers. In the meantime the test can be temporarily disabled until the issue is resolved upstream.

Update: My comment is only valid if the LP file you shared is from the original problem (without the relaxation).

[verheem]

Looks good, big one though. Lets have a discussion tomorrow about how everything is implemented. The code thouches a lot of aspects I can learn about