dev: add docker-compose and sample Kafka producer under examples/

[Jwalasri]

Summary

This PR introduces a self-contained Kafka quickstart example under examples/quickstart-kafka.

Changes

• Added a docker-compose.yml file to spin up Zookeeper and Kafka locally.
• Added a minimal Python producer (producer.py) that sends JSON messages to a demo topic.
• Added a requirements.txt listing the producer dependency (kafka-python).
• Added a README.md with step-by-step instructions to:
  • Start Kafka locally using Docker Compose
  • Produce events using the Python script
  • Consume events using the Kafka console consumer

Why

Currently the repository does not include a simple way for new users to test Kafka end-to-end.
This quickstart lowers the barrier to entry by providing a minimal, reproducible setup for:

• Students learning Kafka basics
• Developers verifying their local environment
• Contributors who want to extend the repo with consumer, streaming, or Spark integrations

Notes

• The example is isolated under examples/quickstart-kafka to avoid impacting core code.
• Users can expand this example by adding consumers, schemas, or Spark pipelines.
• I am happy to update folder naming or content structure if the maintainers prefer a different convention.

Thanks for reviewing 🙏