chore: regenerate Java stubs

chore: regenerate Java stubs

docs: update documentation with ProcessContext and ProcessBuilder

Updated module docstring and README to document all four approaches:
1. Python Wrappers (global process) - for beginners/notebooks
2. ProcessContext - for production/multiple processes
3. ProcessBuilder - fluent API for configuration-driven design
4. Direct Java access - for advanced features

Added code examples for each approach and updated comparison table.