fix ordering and upload new recordings

Signed-off-by: Francisco Javier Arceo <farceo@redhat.com>

llama_stack/core/conversations/conversations.py

@@ -193,12 +193,15 @@ class ConversationServiceImpl(Conversations):
         await self._get_validated_conversation(conversation_id)
 
         created_items = []
-        created_at = int(time.time())
+        base_time = int(time.time())
 
-        for item in items:
+        for i, item in enumerate(items):
             item_dict = item.model_dump()
             item_id = self._get_or_generate_item_id(item, item_dict)
 
+            # make each timestamp unique to maintain order
+            created_at = base_time + i
+
             item_record = {
                 "id": item_id,
                 "conversation_id": conversation_id,