docs(profiles): match the job create response in openapi

The 202 body documented usage_units and a results array. The API returns
entity_count_reserved, event_id and, for sample jobs, entity_ids; results
only appears on GET /v2/profiles/jobs/{id}/. The SDK types already use
entityCountReserved and entityIds, so the spec was the one out of step.

The docs sample example indexes entity_ids with .get(), matching the
notebook and the TS example's ?? [].

docs/platform/features/user-profiles.mdx

@@ -200,7 +200,7 @@ while True:
 print(status["status"], status["succeeded"], "of", status["total"])
 
 # The create response lists the sampled entities; read each one's saved profile.
-for entity_id in job["entity_ids"]:
+for entity_id in job.get("entity_ids", []):
     print(client.get_profile(entity_id))
 ```