Update typing to support snake_case and camelCase through __getattr__

Author: holtskinner

scripts/generate_types.sh

@@ -33,6 +33,9 @@ uv run datamodel-codegen \
   --use-one-literal-as-default \
   --class-name A2A \
   --use-standard-collections \
-  --use-subclass-enum
+  --use-subclass-enum \
+  --snake-case-field \
+  --no-alias
+
 
 echo "Codegen finished successfully."

src/a2a/pydantic_base.py

@@ -1,14 +1,24 @@
 """A2A Pydantic Base Model with shared configuration."""
 
+from typing import Any
+
 from pydantic import BaseModel, ConfigDict
-from pydantic.alias_generators import to_snake
+from pydantic.alias_generators import to_camel, to_snake
 
 
 class A2ABaseModel(BaseModel):
     """Base model for all A2A types with shared configuration."""
 
     model_config = ConfigDict(
-        alias_generator=to_snake,
+        alias_generator=to_camel,
         populate_by_name=True,
-        arbitrary_types_allowed=True,
+        frozen=True,
     )
+
+    def __getattr__(self, name: str) -> Any:
+        snake = to_snake(name)
+        if hasattr(self, snake):
+            return getattr(self, snake)
+        raise AttributeError(
+            f'{type(self).__name__} object has no attribute {name!r}'
+        )