fix: add ruff format post-generation step and apply formatting

- Add 'ruff format' to gen_proto.sh after buf generate
- Apply formatting to a2a_pydantic.py (line-length wrapping for
  long Field() descriptions, consistent blank lines)

Author: brucearctor

scripts/gen_proto.sh

@@ -8,6 +8,10 @@ go install github.com/protocgen/proto2pydantic@v0.5.2
 # Run buf generate to regenerate protobuf code and OpenAPI spec
 npx --yes @bufbuild/buf generate
 
+# Format generated Pydantic models (line-length wrapping for long Field() descriptions)
+echo "Formatting generated Pydantic models..."
+ruff format src/a2a/types/a2a_pydantic.py
+
 # The OpenAPI generator produces a file named like 'a2a.swagger.json' or similar.
 # We need it to be 'a2a.json' for the A2A SDK.
 # Find the generated json file in the output directory