feat(responses): add include parameter (#3115)

Well our Responses tests use it so we better include it in the API, no?

I discovered it because I want to make sure `llama-stack-client` can be
used always instead of `openai-python` as the client (we do want to be
_truly_ compatible.)

docs/_static/llama-stack-spec.html

@@ -8515,6 +8515,13 @@
                             "$ref": "#/components/schemas/OpenAIResponseInputTool"
                         }
                     },
+                    "include": {
+                        "type": "array",
+                        "items": {
+                            "type": "string"
+                        },
+                        "description": "(Optional) Additional fields to include in the response."
+                    },
                     "max_infer_iters": {
                         "type": "integer"
                     }

docs/_static/llama-stack-spec.yaml

@@ -6188,6 +6188,12 @@ components:
           type: array
           items:
             $ref: '#/components/schemas/OpenAIResponseInputTool'
+        include:
+          type: array
+          items:
+            type: string
+          description: >-
+            (Optional) Additional fields to include in the response.
         max_infer_iters:
           type: integer
       additionalProperties: false

llama_stack/apis/agents/agents.py

@@ -706,6 +706,7 @@ class Agents(Protocol):
         temperature: float | None = None,
         text: OpenAIResponseText | None = None,
         tools: list[OpenAIResponseInputTool] | None = None,
+        include: list[str] | None = None,
         max_infer_iters: int | None = 10,  # this is an extension to the OpenAI API
     ) -> OpenAIResponseObject | AsyncIterator[OpenAIResponseObjectStream]:
         """Create a new OpenAI response.
@@ -713,6 +714,7 @@ class Agents(Protocol):
         :param input: Input message(s) to create the response.
         :param model: The underlying LLM used for completions.
         :param previous_response_id: (Optional) if specified, the new response will be a continuation of the previous response. This can be used to easily fork-off new responses from existing responses.
+        :param include: (Optional) Additional fields to include in the response.
         :returns: An OpenAIResponseObject.
         """
         ...

llama_stack/providers/inline/agents/meta_reference/agents.py

@@ -327,10 +327,21 @@ class MetaReferenceAgentsImpl(Agents):
         temperature: float | None = None,
         text: OpenAIResponseText | None = None,
         tools: list[OpenAIResponseInputTool] | None = None,
+        include: list[str] | None = None,
         max_infer_iters: int | None = 10,
     ) -> OpenAIResponseObject:
         return await self.openai_responses_impl.create_openai_response(
-            input, model, instructions, previous_response_id, store, stream, temperature, text, tools, max_infer_iters
+            input,
+            model,
+            instructions,
+            previous_response_id,
+            store,
+            stream,
+            temperature,
+            text,
+            tools,
+            include,
+            max_infer_iters,
         )
 
     async def list_openai_responses(

llama_stack/providers/inline/agents/meta_reference/openai_responses.py

@@ -333,6 +333,7 @@ class OpenAIResponsesImpl:
         temperature: float | None = None,
         text: OpenAIResponseText | None = None,
         tools: list[OpenAIResponseInputTool] | None = None,
+        include: list[str] | None = None,
         max_infer_iters: int | None = 10,
     ):
         stream = bool(stream)