Fix token counts in OpenAI Agents redux (#890)

* Update attribute extraction to support dict as well as object.

* Adjust tests to match serialization format of `list[str]`. Patch JSON encode in tests to handle MagicMock objects.

* Collect base usage attributes, too.

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Co-authored-by: Pratyush Shukla <[email protected]>

Author: tcdent

agentops/instrumentation/openai_agents/attributes/response.py

@@ -294,6 +294,10 @@ def get_response_usage_attributes(usage: 'ResponseUsage') -> AttributeMap:
     # )
     attributes = {}
 
+    attributes.update(_extract_attributes_from_mapping(
+        usage.__dict__,
+        RESPONSE_USAGE_ATTRIBUTES))
+    
     # input_tokens_details is a dict if it exists
     if hasattr(usage, 'input_tokens_details'):
         input_details = usage.input_tokens_details