feat: add list responses API (#2233)

# What does this PR do?
This is not part of the official OpenAI API, but we'll use this for the
logs UI.
In order to support more filtering options, I'm adopting the newly
introduced sql store in in place of the kv store.

## Test Plan
Added integration/unit tests.

llama_stack/providers/inline/agents/meta_reference/agents.py

@@ -20,9 +20,11 @@ from llama_stack.apis.agents import (
     AgentTurnCreateRequest,
     AgentTurnResumeRequest,
     Document,
+    ListOpenAIResponseObject,
     OpenAIResponseInput,
     OpenAIResponseInputTool,
     OpenAIResponseObject,
+    Order,
     Session,
     Turn,
 )
@@ -39,6 +41,7 @@ from llama_stack.apis.tools import ToolGroups, ToolRuntime
 from llama_stack.apis.vector_io import VectorIO
 from llama_stack.providers.utils.kvstore import InmemoryKVStoreImpl, kvstore_impl
 from llama_stack.providers.utils.pagination import paginate_records
+from llama_stack.providers.utils.responses.responses_store import ResponsesStore
 
 from .agent_instance import ChatAgent
 from .config import MetaReferenceAgentsImplConfig
@@ -66,15 +69,17 @@ class MetaReferenceAgentsImpl(Agents):
         self.tool_groups_api = tool_groups_api
 
         self.in_memory_store = InmemoryKVStoreImpl()
-        self.openai_responses_impl = None
+        self.openai_responses_impl: OpenAIResponsesImpl | None = None
 
     async def initialize(self) -> None:
         self.persistence_store = await kvstore_impl(self.config.persistence_store)
+        self.responses_store = ResponsesStore(self.config.responses_store)
+        await self.responses_store.initialize()
         self.openai_responses_impl = OpenAIResponsesImpl(
-            self.persistence_store,
             inference_api=self.inference_api,
             tool_groups_api=self.tool_groups_api,
             tool_runtime_api=self.tool_runtime_api,
+            responses_store=self.responses_store,
         )
 
     async def create_agent(
@@ -323,3 +328,12 @@ class MetaReferenceAgentsImpl(Agents):
         return await self.openai_responses_impl.create_openai_response(
             input, model, instructions, previous_response_id, store, stream, temperature, tools
         )
+
+    async def list_openai_responses(
+        self,
+        after: str | None = None,
+        limit: int | None = 50,
+        model: str | None = None,
+        order: Order | None = Order.desc,
+    ) -> ListOpenAIResponseObject:
+        return await self.openai_responses_impl.list_openai_responses(after, limit, model, order)