Add sklearn-java to Machine Learning section

[kundanjan]

Description

Adds sklearn-java to the Machine Learning section — a pure Java reimplementation of scikit-learn's API.

• Apache 2.0 license
• 72+ sklearn algorithms implemented (linear models, trees, ensembles, SVM, preprocessing, metrics, model selection, clustering, naive bayes, neighbors)
• API mirrors sklearn exactly: .fit(), .predict(), .transform(), .score()
• 190+ JUnit 5 tests passing
• Numerical accuracy validated against Python sklearn to 1e-8

Let me know if any changes are needed!

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Summary by cubic

Added sklearn-java to the Machine Learning section.

Pure Java reimplementation of scikit-learn’s API with 70+ algorithms, Apache 2.0 license, and 1e-8 numerical accuracy.

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[cubic-dev-ai]

No issues found across 1 file

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