use crate::{    db::UserId,    llm::db::{BillingEventId, ModelId},};use sea_orm::entity::prelude::*; #[derive(Clone, Debug, PartialEq, DeriveEntityModel)]#[sea_orm(table_name = "billing_events")]pub struct Model {    #[sea_orm(primary_key)]    pub id: BillingEventId,    pub idempotency_key: Uuid,    pub user_id: UserId,    pub model_id: ModelId,    pub input_tokens: i64,    pub input_cache_creation_tokens: i64,    pub input_cache_read_tokens: i64,    pub output_tokens: i64,} #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]pub enum Relation {    #[sea_orm(        belongs_to = "super::model::Entity",        from = "Column::ModelId",        to = "super::model::Column::Id"    )]    Model,} impl Related<super::model::Entity> for Entity {    fn to() -> RelationDef {        Relation::Model.def()    }} impl ActiveModelBehavior for ActiveModel {}