Add comprehensive test coverage

When introducing new functionality, always include corresponding test coverage that extends existing test infrastructure and validates the feature across multiple scenarios. This ensures robustness and maintains code quality standards.

Key practices:

• Extend existing test utilities and infrastructure rather than creating isolated tests
• Write integration tests that validate end-to-end functionality
• Test across different configurations and edge cases
• Follow established testing patterns in the codebase

Example approach:

# When adding streaming functionality, extend existing test server
# tests/test_utils/server/litellm_server.py - add streaming endpoint

# Create integration test in appropriate location
# tests/streaming.py
def test_streaming_endpoint():
    # Use existing test infrastructure like litellm_test_server
    # Test the complete flow: configure -> run program -> validate stream
    stream = streaming_dspy_program(question=question.text)
    # Validate streaming response format and content

This approach ensures that new features are thoroughly validated and integrate seamlessly with existing systems, reducing the likelihood of regressions and improving overall system reliability.