convert _default_params to dataclass

[Borda]

improve readability and reduce eventual typo errors while manipulating keys

with IDE it is now feasible to track usage
also suggesting to rename default_params to global_params as it is better fit

[shaypal5]

Ok, I let GitHub merge the pre-commit.ci fix into this branch, and it now works, but fails. :)

[Borda]

Ok, I let GitHub merge the pre-commit.ci fix into this branch, and it now works, but fails. :)

@shaypal5 done and resolved last linting issue

[shaypal5]

Great! I love the new data class, and the deprecation warning. Let's remember to bump the major part of the version number when we push out the breaking change of delete the set_deafult_params method and any of its friends.