Improve error handling

[timmens]

This PR's goal is to run tranquilo on the More and Wild benchmark set without raising any errors.

More broadly, we want that

• Any invalid return (or exception) of the criterion functions is intercepted and replaced with infinity
• Any appearance of infinity is handled correctly

For this, I

1. Set function evaluations that raise an exception to infinity in the wrapped criterion function

2. Check that the candidate point of the acceptance step is valid (does not correspond to a criterion value of infinity), and otherwise return the current best point and a rho of negative infinity

3. Add error handling around the subsolvers by adding a fallback solver that is activated if the regular subsolver raises an exception. Currently, implemented fallback options are:
   Sphere

   • SLSQP with a nonlinear constraint corresponding to $|| x || \leq 1$
   • L-BFGS-B with a box constraint equal to the largest box inscribed in the unit sphere
   • L-BFGS-B with parametrization (project $x$ onto the sphere hull if $||x|| > 1$)

   Cube

   • L-BFGS-B with a box constraint $-1 \leq x \leq 1$
   • L-BFGS-B with a box constraint in a multistart framework

Additionally, I

1. Skip the poisedness tests on windows, as they are instable and not used currently.

[codecov]

Codecov Report

Attention: 10 lines in your changes are missing coverage. Please review.

Comparison is base (7042550) 77.91% compared to head (398d14b) 78.48%.

Files	Patch %	Lines
src/tranquilo/acceptance_decision.py	44.44%	5 Missing ⚠️
src/tranquilo/solve_subproblem.py	73.33%	4 Missing ⚠️
src/tranquilo/subsolvers/fallback_subsolvers.py	98.36%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main       #8      +/-   ##
==========================================
+ Coverage   77.91%   78.48%   +0.57%     
==========================================
  Files          68       68              
  Lines        4881     4923      +42     
==========================================
+ Hits         3803     3864      +61     
+ Misses       1078     1059      -19     

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