fix: signature change to match OpenAI SDK

docs/_static/llama-stack-spec.yaml

@@ -963,7 +963,7 @@ paths:
           required: true
           schema:
             type: string
-  /v1/openai/v1/responses/{id}:
+  /v1/openai/v1/responses/{response_id}:
     get:
       responses:
         '200':
@@ -986,7 +986,7 @@ paths:
         - Agents
       description: Retrieve an OpenAI response by its ID.
       parameters:
-        - name: id
+        - name: response_id
           in: path
           description: >-
             The ID of the OpenAI response to retrieve.