feat(admin): art-design-pro integration with local session auth

P1b Task 9: apps/admin based on art-design-pro v3.0.2 (tag, commit
d224dd4; source recorded in apps/admin/SOURCE.md), trimmed to
layout/login/i18n/request/table-form core. Login wired to real
POST /v1/auth/password (single-token session), Bearer header on all
requests, 401 interceptor logout+redirect, request-driven sliding
renewal (refresh at ~80% TTL, single-flight), best-effort
POST /v1/auth/logout on user-menu logout. One protected stub page
(相册管理). Dev port 5176 strictPort + /v1 proxy to 8080. Admin keeps
its own eslint9 flat config; root eslint ignores apps/admin/**.
vitest unit tests for renewal pacing + Playwright e2e (guard redirect,
localized wrong-password error, login lands on stub, token persists
across reload, logout clears session).

Co-Authored-By: Claude Code <noreply@anthropic.com>

apps/admin/playwright.config.ts

@@ -0,0 +1,35 @@
+import { defineConfig, devices } from '@playwright/test'
+
+// 同 apps/viewer 约定：webServer 先等 API（8080，仓库根 `pnpm dev:api` 构建+启动，
+// 已在跑的实例直接复用），再等 admin dev（5176，/v1 代理 → 8080）。
+// globalSetup 幂等种子管理员（services/api seed：ADMIN_ACCOUNT/ADMIN_PASSWORD，
+// 账号已存在则跳过且不改写密码）。compose 基础设施需预先 `docker compose up -d`。
+export default defineConfig({
+  testDir: './e2e',
+  timeout: 60_000,
+  // dev server 首次按需编译 + 动态路由初始化较慢，放宽断言超时（默认 5s 偏紧）
+  expect: { timeout: 20_000 },
+  fullyParallel: true,
+  reporter: [['list']],
+  use: {
+    baseURL: 'http://127.0.0.1:5176',
+    trace: 'on-first-retry'
+  },
+  projects: [{ name: 'chromium', use: { ...devices['Desktop Chrome'] } }],
+  globalSetup: './e2e/global-setup.ts',
+  webServer: [
+    {
+      command: 'pnpm dev:api',
+      cwd: '../..',
+      url: 'http://127.0.0.1:8080/v1/health',
+      reuseExistingServer: true,
+      timeout: 180_000 // 首次含 tsc 全量构建
+    },
+    {
+      command: 'pnpm run dev',
+      url: 'http://127.0.0.1:5176',
+      reuseExistingServer: true,
+      timeout: 120_000 // 首次含依赖预构建
+    }
+  ]
+})