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/src/App.vue

@@ -0,0 +1,39 @@
+<template>
+  <ElConfigProvider
+    size="default"
+    :locale="locales[language]"
+    :z-index="3000"
+    :card="{
+      shadow: 'never'
+    }"
+  >
+    <RouterView></RouterView>
+  </ElConfigProvider>
+</template>
+
+<script setup lang="ts">
+  import { useUserStore } from './store/modules/user'
+  import zh from 'element-plus/es/locale/lang/zh-cn'
+  import en from 'element-plus/es/locale/lang/en'
+  import { toggleTransition } from './utils/ui/animation'
+  import { checkStorageCompatibility } from './utils/storage'
+  import { initializeTheme } from './hooks/core/useTheme'
+
+  const userStore = useUserStore()
+  const { language } = storeToRefs(userStore)
+
+  const locales = {
+    zh: zh,
+    en: en
+  }
+
+  onBeforeMount(() => {
+    toggleTransition(true)
+    initializeTheme()
+  })
+
+  onMounted(() => {
+    checkStorageCompatibility()
+    toggleTransition(false)
+  })
+</script>