docs: document streaming iterator guardrail

docs/my-website/docs/providers/ollama.md

@@ -240,7 +240,7 @@ model_list:
 ```bash
 litellm --config /path/to/config.yaml --detailed_debug
 
-# RUNNING ON http://0.0.0.0:4000
+# RUNNING ON http://0.0.0.0:4000 
 ```
 
 3. Test it! 

docs/my-website/docs/proxy/guardrails/custom_guardrail.md

@@ -128,6 +128,21 @@ class myCustomGuardrail(CustomGuardrail):
                     ):
                         raise ValueError("Guardrail failed Coffee Detected")
 
+    async def async_post_call_streaming_iterator_hook(
+        self,
+        user_api_key_dict: UserAPIKeyAuth,
+        response: Any,
+        request_data: dict,
+    ) -> AsyncGenerator[ModelResponseStream, None]:
+        """
+        Passes the entire stream to the guardrail
+
+        This is useful for guardrails that need to see the entire response, such as PII masking.
+
+        See Aim guardrail implementation for an example - https://github.com/BerriAI/litellm/blob/d0e022cfacb8e9ebc5409bb652059b6fd97b45c0/litellm/proxy/guardrails/guardrail_hooks/aim.py#L168
+        """
+        async for item in response:
+            yield item
 
 ```