feat(python): add native distribution and release infrastructure

- add the Rust-backed Python API with PyStemmer compatibility
- distribute standard compiled models as a separate Python package
- generate model artifacts during builds instead of storing them in Git
- add GitHub release and Pages-backed package index workflows
- add Python tests, benchmarks, documentation, and Gradle integration
- refresh the documentation site, branding, and language benchmarks

python/models-standard/MANIFEST.in

@@ -0,0 +1,4 @@
+include LICENSE-MODEL-DATA.txt
+include README.md
+recursive-include radixor_models_standard *.json *.rxc *.txt
+global-exclude stemmer.gz *.gz __pycache__ *.py[cod]