Fix: resolve scipy.stats imports for compatibility

[ghost]

Description

This pull request updates the drift detection code to improve compatibility with Python 3.12+. Specifically:

• Ensures that imports for scipy.stats functions (chi2, ks_2samp, wasserstein_distance) and KstestResult are up to date.
• Adjusts _calculate_ks function type hints to use KstestResult.
• Validates datasets and columns more robustly, including checks for empty series and identical datasets.
• Cleans up redundant imports and prepares the code for Python 3.13+.

These changes do not alter the core drift calculation logic, which includes:

• Categorical drift: PSI and Chi-Squared tests
• Numerical drift: KS test and Earth Mover’s Distance
• Prediction drift: PSI, Chi-Squared, KS, and EMD for classification and regression models

The code has not yet been fully tested on Python 3.13, so further testing is required to confirm full compatibility.

Related Issue

N/A

Type of Change

• 📚 Examples / docs / tutorials / dependencies update
• 🔧 Bug fix (non-breaking change which fixes an issue)
• 🥂 Improvement (preparation for future Python compatibility)
• 🚀 New feature (non-breaking change which adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to change)
• 🔐 Security fix

Checklist

• I've read the CODE_OF_CONDUCT.md document.
• I've read the CONTRIBUTING.md guide.
• I've written tests for all new methods and classes that I created. (Not applicable, only imports updated / compatibility improvements)
• I've updated the docstrings in Google format where needed. (No functional changes made)
• I've updated the pdm.lock by running pdm update-lock if dependencies changed. (Not applicable)

[kevinmessiaen]

Thanks for your fix @kaiprvn

This look good, let's just run pre-commit hook to ensure proper code formatting