Polish the algo selection tool

[janosg]

• Create a better string representation for algorithm classes
• Allow algorithm classes and instances as dict keys in the results dict for criterion_plot

[codecov]

Codecov Report

Attention: Patch coverage is 87.50000% with 8 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/optimagic/optimization/algorithm.py	80.00%	4 Missing ⚠️
src/optimagic/optimizers/pygmo_optimizers.py	33.33%	2 Missing ⚠️
src/optimagic/optimizers/tao_optimizers.py	33.33%	2 Missing ⚠️

Files with missing lines	Coverage Δ
src/estimagic/__init__.py	96.36% <ø> (-0.31%)	⬇️
src/optimagic/__init__.py	100.00% <ø> (ø)
src/optimagic/algorithms.py	85.68% <100.00%> (+0.10%)	⬆️
src/optimagic/visualization/history_plots.py	90.72% <100.00%> (+0.80%)	⬆️
src/optimagic/optimizers/pygmo_optimizers.py	94.48% <33.33%> (-0.49%)	⬇️
src/optimagic/optimizers/tao_optimizers.py	74.28% <33.33%> (-1.68%)	⬇️
src/optimagic/optimization/algorithm.py	94.79% <80.00%> (-1.77%)	⬇️