safety, chore: async inference store write

# What does this PR do?


## Test Plan
# What does this PR do?


## Test Plan

docs/source/distributions/k8s-benchmark/stack_run_config.yaml

@@ -3,6 +3,7 @@ image_name: kubernetes-benchmark-demo
 apis:
 - agents
 - inference
+- safety
 - telemetry
 - tool_runtime
 - vector_io
@@ -30,6 +31,11 @@ providers:
         db: ${env.POSTGRES_DB:=llamastack}
         user: ${env.POSTGRES_USER:=llamastack}
         password: ${env.POSTGRES_PASSWORD:=llamastack}
+  safety:
+  - provider_id: llama-guard
+    provider_type: inline::llama-guard
+    config:
+      excluded_categories: []
   agents:
   - provider_id: meta-reference
     provider_type: inline::meta-reference
@@ -95,6 +101,8 @@ models:
 - model_id: ${env.INFERENCE_MODEL}
   provider_id: vllm-inference
   model_type: llm
+shields:
+- shield_id: ${env.SAFETY_MODEL:=meta-llama/Llama-Guard-3-1B}
 vector_dbs: []
 datasets: []
 scoring_fns: []

llama_stack/core/routers/inference.py

@@ -527,7 +527,7 @@ class InferenceRouter(Inference):
 
         # Store the response with the ID that will be returned to the client
         if self.store:
-            await self.store.store_chat_completion(response, messages)
+            asyncio.create_task(self.store.store_chat_completion(response, messages))
 
         if self.telemetry:
             metrics = self._construct_metrics(
@@ -855,4 +855,4 @@ class InferenceRouter(Inference):
                     object="chat.completion",
                 )
                 logger.debug(f"InferenceRouter.completion_response: {final_response}")
-                await self.store.store_chat_completion(final_response, messages)
+                asyncio.create_task(self.store.store_chat_completion(final_response, messages))