Improve typing in fmudesign

After adding type annotations to the `fmudesign` module, i noticed that some types was too narrow and resulted in type check violations for another repo i was working on.

The relevant places is:

* `fmudesign.design_distributions.draw_values()` (and `draw_values_DISTTYPE`): Type of `dist_parameters` should be `Sequence[str | float]`, as it accepts both string and floats and eventually converts it to float

* `fmudesign.create_design.is_consistent_correlation_matrix()`: Type of `matrix` works with `pandas.DataFrame`, and should be widened to also accept it.

I can create a PR that fixes this Soon™️

Start with fmudesign.design_distributions.draw_values() and draw_values_DISTTYPE(), then inspect fmudesign.create_design.is_consistent_correlation_matrix(). Confirm the accepted types match the issue, including strings and floats for dist_parameters and pandas.DataFrame for matrix, and verify that type checking no longer reports the described violations.

Written by the indexing model from the issue text.