a2a-java

Analyzes and fixes A2A Transport Compatibility Kit (TCK) issues by understanding the specification, reproducing the failure, implementing the fix, and validating it works.

Update the A2A Protobuf file (a2a.proto) when the A2A protocol specification changes. Use when the user mentions updating the spec, syncing with upstream A2A, or when a new version of the A2A protocol is released.