test(frontend): align admin usage typing with upstream model

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

frontend/src/types/index.ts

@@ -978,7 +978,6 @@ export interface UsageLog {
   account_id: number | null
   request_id: string
   model: string
-  upstream_model?: string | null
   service_tier?: string | null
   reasoning_effort?: string | null
   inbound_endpoint?: string | null
@@ -1033,6 +1032,8 @@ export interface UsageLogAccountSummary {
 }
 
 export interface AdminUsageLog extends UsageLog {
+  upstream_model?: string | null
+
   // 账号计费倍率（仅管理员可见）
   account_rate_multiplier?: number | null