feat: funciones Python para core, cybersecurity, datascience y finance

Agrega funciones Python reutilizables organizadas por dominio:
- core: composicion funcional (pipe, compose, map, filter, reduce, etc.)
- cybersecurity: analisis de amenazas y puertos
- datascience: estadisticas y deteccion de outliers
- finance: indicadores tecnicos y analisis financiero

python/functions/datascience/pearson.md

@@ -0,0 +1,32 @@
+---
+name: pearson
+kind: function
+lang: py
+domain: datascience
+version: "1.0.0"
+purity: pure
+signature: "def pearson(xs: list, ys: list) -> float"
+description: "Calcula el coeficiente de correlacion de Pearson entre dos listas de floats."
+tags: [statistics, correlation, python]
+uses_functions: []
+uses_types: []
+returns: []
+returns_optional: false
+error_type: ""
+imports: [math]
+tested: false
+tests: []
+test_file_path: ""
+file_path: "python/functions/datascience/datascience.py"
+---
+
+## Ejemplo
+
+```python
+r = pearson([1, 2, 3], [2, 4, 6])
+# r = 1.0
+```
+
+## Notas
+
+Usa solo math stdlib. No requiere numpy. Retorna 0.0 si las listas tienen longitud diferente, estan vacias, o la desviacion es cero.