Task: Update README.md to reflect recent changes in NATSbridge package.

Context: the package has been updated with the NATS_connection keyword and the publish_message function.

Requirements:

Source of Truth: Treat the updated NATSbridge code as the definitive source. Update README.md to align exactly with these changes.
API Consistency: Ensure the Main Package API (e.g., smartsend(), publish_message()) uses consistent naming across all three supported languages.
Ecosystem Variance: Low-level native functions (e.g., NATS.connect(), JSON.read()) should follow the conventions of the specific language ecosystem and do not require cross-language consistency.