perf(usage): 将 status 过滤下推到 SQL 查询层

为 UsageAuditListQuery 新增 statuses 字段，支持在数据库端按状态
筛选用量记录。admin usage summary 路由不再全量拉取后内存过滤，
改为直接查询 pending/streaming 状态的记录。

crates/aether-data-contracts/src/repository/usage/types.rs

@@ -480,6 +480,7 @@ pub struct UsageAuditListQuery {
     pub user_id: Option<String>,
     pub provider_name: Option<String>,
     pub model: Option<String>,
+    pub statuses: Option<Vec<String>>,
 }
 
 #[derive(Debug, Clone, PartialEq, Default, serde::Serialize, serde::Deserialize)]