The reactive, non-blocking version of Module 01 using Project Reactor.
Full tutorial: https://lab.pollack.ai/docs/acp-java-sdk/tutorial/21-async-client
Requires the Grok CLI on your PATH, signed in once with grok login.
The module launches it as grok agent stdio; no API key is needed.
./mvnw compile exec:java -pl module-21-async-client