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>

eslint.config.js

@@ -22,6 +22,10 @@ module.exports = tseslint.config(
       '**/playwright-report/',
       '**/test-results/',
       '**/blob-report/',
+      // apps/admin（P1b Task 9，art-design-pro 模板）自带 eslint9 flat config
+      // （eslint.config.mjs + prettier/stylelint 规则集），与根配置的规则集不同；
+      // 计划「执行注意」注册的偏差：根配置不覆盖 admin，admin `lint` 脚本跑自己的配置。
+      'apps/admin/**',
     ],
   },
   ...tseslint.configs.recommended,