docs(raw_request_prod.md): add seeing raw request / response for proxy on docs

docs/my-website/docs/observability/raw_request_response.md

@@ -4,6 +4,7 @@ import Image from '@theme/IdealImage';
 
 See the raw request/response sent by LiteLLM in your logging provider (OTEL/Langfuse/etc.).
 
+**on SDK**
 ```python
 # pip install langfuse 
 import litellm
@@ -33,6 +34,13 @@ response = litellm.completion(
 )
 ```
 
+**on Proxy**
+
+```yaml
+litellm_settings:
+  log_raw_request_response: True
+```
+
 **Expected Log**
 
 <Image img={require('../../img/raw_request_log.png')}/>