feat: add size async caching (#2532)

letta/orm/passage.py

@@ -90,4 +90,8 @@ class AgentPassage(BasePassage, AgentMixin):
                 Index("agent_passages_created_at_id_idx", "created_at", "id"),
                 {"extend_existing": True},
             )
-        return (Index("agent_passages_created_at_id_idx", "created_at", "id"), {"extend_existing": True})
+        return (
+            Index("ix_agent_passages_org_agent", "organization_id", "agent_id"),
+            Index("agent_passages_created_at_id_idx", "created_at", "id"),
+            {"extend_existing": True},
+        )

letta/orm/sqlalchemy_base.py

@@ -840,7 +840,7 @@ class SqlalchemyBase(CommonSqlalchemyMetaMixins, Base):
         **kwargs,
     ):
         logger.debug(f"Calculating size for {cls.__name__} with filters {kwargs}")
-        query = select(func.count()).select_from(cls)
+        query = select(func.count(1)).select_from(cls)
 
         if actor:
             query = cls.apply_access_predicate(query, actor, access, access_type)