refactor(saas): 架构重构 + 性能优化 — 借鉴 loco-rs 模式

Phase 0: 知识库
- docs/knowledge-base/loco-rs-patterns.md — loco-rs 10 个可借鉴模式研究

Phase 1: 数据层重构
- crates/zclaw-saas/src/models/ — 15 个 FromRow 类型化模型
- Login 3 次查询合并为 1 次 AccountLoginRow 查询
- 所有 service 文件从元组解构迁移到 FromRow 结构体

Phase 2: Worker + Scheduler 系统
- crates/zclaw-saas/src/workers/ — Worker trait + 5 个具体实现
- crates/zclaw-saas/src/scheduler.rs — TOML 声明式调度器
- crates/zclaw-saas/src/tasks/ — CLI 任务系统

Phase 3: 性能修复
- Relay N+1 查询 → 精准 SQL (relay/handlers.rs)
- Config RwLock → AtomicU32 无锁 rate limit (state.rs, middleware.rs)
- SSE std::sync::Mutex → tokio::sync::Mutex (relay/service.rs)
- /auth/refresh 阻塞清理 → Scheduler 定期执行

Phase 4: 多环境配置
- config/saas-{development,production,test}.toml
- ZCLAW_ENV 环境选择 + ZCLAW_SAAS_CONFIG 精确覆盖
- scheduler 配置集成到 TOML

admin/src/app/(dashboard)/api-keys/page.tsx

@@ -35,7 +35,7 @@ import {
 import { api } from '@/lib/api-client'
 import { ErrorBanner, EmptyState } from '@/components/ui/state'
 import { ApiRequestError } from '@/lib/api-client'
-import { formatDate } from '@/lib/utils'
+import { formatDate, getSwrErrorMessage } from '@/lib/utils'
 import { TableSkeleton } from '@/components/ui/skeleton'
 import type { TokenInfo } from '@/lib/types'
 
@@ -58,7 +58,7 @@ export default function ApiKeysPage() {
 
   const tokens = data?.items ?? []
   const total = data?.total ?? 0
-  const error = swrError?.message || mutationError
+  const error = getSwrErrorMessage(swrError) || mutationError
 
   // 创建 Dialog
   const [createOpen, setCreateOpen] = useState(false)