Development Type generation from spec uv run datamodel-codegen \ --url https://raw.githubusercontent.com/google-a2a/A2A/refs/heads/main/specification/json/a2a.json \ --input-file-type jsonschema \ --output ./src/a2a/types.py \ --target-python-version 3.10 \ --output-model-type pydantic_v2.BaseModel \ --disable-timestamp \ --use-schema-description \ --use-union-operator \ --use-field-description \ --use-default \ --use-default-kwarg \ --use-one-literal-as-default \ --class-name A2A \ --use-standard-collections \ --use-subclass-enum