feat(admin-web): 登录页 + Auth Guard + API URL 切换域名

- 新建 /login 页面（邮箱/密码登录，对接 auth-context）
- AdminLayout 添加 auth guard：未登录自动跳转 /login
- api-client 默认 URL 从 localhost:8080 → https://api.gogenex.com
- Header 头像显示用户首字母，点击登出
- i18n 补充 header_logout (zh/en/ja)

API 联通验证（全部正常）:
- POST /api/v1/auth/sms/send → 400 (手机号未注册)
- POST /api/v1/auth/login → 401 (密码错误)
- POST /api/v1/auth/register → 400 (验证码过期)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/admin-web/src/app/login/page.tsx

@@ -0,0 +1,157 @@
+'use client';
+
+import React, { useState, FormEvent } from 'react';
+import { useRouter } from 'next/navigation';
+import Image from 'next/image';
+import { useAuth } from '@/lib/auth-context';
+
+export default function LoginPage() {
+  const router = useRouter();
+  const { login, isAuthenticated } = useAuth();
+  const [email, setEmail] = useState('');
+  const [password, setPassword] = useState('');
+  const [error, setError] = useState('');
+  const [loading, setLoading] = useState(false);
+
+  // 已登录则跳转
+  if (isAuthenticated) {
+    router.replace('/dashboard');
+    return null;
+  }
+
+  const handleSubmit = async (e: FormEvent) => {
+    e.preventDefault();
+    setError('');
+    setLoading(true);
+    try {
+      await login(email, password);
+      router.replace('/dashboard');
+    } catch (err: unknown) {
+      const msg =
+        (err as { response?: { data?: { message?: string } } })?.response?.data
+          ?.message || '登录失败，请检查账号密码';
+      setError(msg);
+    } finally {
+      setLoading(false);
+    }
+  };
+
+  return (
+    <div style={styles.wrapper}>
+      <div style={styles.card}>
+        <div style={styles.logoRow}>
+          <Image src="/logo.svg" alt="Genex" width={40} height={40} />
+          <span style={styles.brand}>Genex Admin</span>
+        </div>
+        <h1 style={styles.title}>管理后台登录</h1>
+
+        <form onSubmit={handleSubmit} style={styles.form}>
+          <label style={styles.label}>邮箱 / 手机号</label>
+          <input
+            style={styles.input}
+            type="text"
+            placeholder="admin@gogenex.com"
+            value={email}
+            onChange={(e) => setEmail(e.target.value)}
+            required
+            autoFocus
+          />
+
+          <label style={styles.label}>密码</label>
+          <input
+            style={styles.input}
+            type="password"
+            placeholder="请输入密码"
+            value={password}
+            onChange={(e) => setPassword(e.target.value)}
+            required
+          />
+
+          {error && <p style={styles.error}>{error}</p>}
+
+          <button type="submit" style={styles.btn} disabled={loading}>
+            {loading ? '登录中...' : '登录'}
+          </button>
+        </form>
+
+        <p style={styles.footer}>Genex 券金融平台 &copy; 2025</p>
+      </div>
+    </div>
+  );
+}
+
+/* ---------- inline styles (no extra CSS file) ---------- */
+const styles: Record<string, React.CSSProperties> = {
+  wrapper: {
+    display: 'flex',
+    justifyContent: 'center',
+    alignItems: 'center',
+    minHeight: '100vh',
+    background: 'linear-gradient(135deg, #F3F1FF 0%, #E8E5FF 50%, #F8F9FC 100%)',
+  },
+  card: {
+    width: 400,
+    padding: '40px 36px',
+    borderRadius: 16,
+    background: '#fff',
+    boxShadow: '0 8px 32px rgba(108,92,231,0.10)',
+  },
+  logoRow: {
+    display: 'flex',
+    alignItems: 'center',
+    gap: 10,
+    marginBottom: 8,
+  },
+  brand: {
+    fontSize: 20,
+    fontWeight: 700,
+    color: '#6C5CE7',
+  },
+  title: {
+    fontSize: 24,
+    fontWeight: 600,
+    color: '#262B3A',
+    margin: '16px 0 28px',
+  },
+  form: {
+    display: 'flex',
+    flexDirection: 'column' as const,
+    gap: 12,
+  },
+  label: {
+    fontSize: 14,
+    fontWeight: 500,
+    color: '#5C6478',
+  },
+  input: {
+    padding: '10px 14px',
+    fontSize: 15,
+    border: '1px solid #E4E7F0',
+    borderRadius: 8,
+    outline: 'none',
+    transition: 'border-color 0.2s',
+  },
+  error: {
+    fontSize: 13,
+    color: '#FF4757',
+    margin: 0,
+  },
+  btn: {
+    marginTop: 8,
+    padding: '12px 0',
+    fontSize: 16,
+    fontWeight: 600,
+    color: '#fff',
+    background: '#6C5CE7',
+    border: 'none',
+    borderRadius: 8,
+    cursor: 'pointer',
+    transition: 'opacity 0.2s',
+  },
+  footer: {
+    textAlign: 'center' as const,
+    marginTop: 28,
+    fontSize: 12,
+    color: '#A0A8BE',
+  },
+};

frontend/admin-web/src/i18n/locales.ts

@@ -134,6 +134,7 @@ const translations: Record<Locale, Record<string, string>> = {
     // ── Header ──
     'header_search_placeholder': '搜索用户/订单/交易...',
     'header_ai_assistant': 'AI 助手',
+    'header_logout': '退出登录',
 
     // ── Dashboard ──
     'dashboard_title': '运营总览',
@@ -866,6 +867,7 @@ const translations: Record<Locale, Record<string, string>> = {
     // ── Header ──
     'header_search_placeholder': 'Search users/orders/trades...',
     'header_ai_assistant': 'AI Assistant',
+    'header_logout': 'Logout',
 
     // ── Dashboard ──
     'dashboard_title': 'Dashboard',
@@ -1598,6 +1600,7 @@ const translations: Record<Locale, Record<string, string>> = {
     // ── Header ──
     'header_search_placeholder': 'ユーザー/注文/取引を検索...',
     'header_ai_assistant': 'AIアシスタント',
+    'header_logout': 'ログアウト',
 
     // ── Dashboard ──
     'dashboard_title': '運営概要',

frontend/admin-web/src/layouts/AdminLayout.tsx

@@ -4,6 +4,7 @@ import React, { useState } from 'react';
 import { usePathname, useRouter } from 'next/navigation';
 import Link from 'next/link';
 import { t } from '@/i18n/locales';
+import { useAuth } from '@/lib/auth-context';
 
 /**
  * D. Web管理前端 - 主布局
@@ -95,8 +96,17 @@ const navItems: NavItem[] = [
 export const AdminLayout: React.FC<{ children: React.ReactNode }> = ({ children }) => {
   const pathname = usePathname();
   const router = useRouter();
+  const { isAuthenticated, isLoading, user, logout } = useAuth();
   const [collapsed, setCollapsed] = useState(false);
 
+  // 未登录 → /login
+  if (!isLoading && !isAuthenticated) {
+    router.replace('/login');
+    return null;
+  }
+  // 加载中显示空白
+  if (isLoading) return null;
+
   // Derive activeKey from current pathname
   const activeKey = pathname.replace(/^\//, '') || 'dashboard';
 
@@ -324,7 +334,17 @@ export const AdminLayout: React.FC<{ children: React.ReactNode }> = ({ children
                 borderRadius: '50%',
               }} />
             </button>
-            {/* Admin avatar */}
+            {/* Admin avatar + logout */}
+            <div
+              style={{
+                display: 'flex',
+                alignItems: 'center',
+                gap: 8,
+                cursor: 'pointer',
+              }}
+              onClick={logout}
+              title={t('header_logout')}
+            >
               <div style={{
                 width: 32, height: 32,
                 borderRadius: '50%',
@@ -336,7 +356,8 @@ export const AdminLayout: React.FC<{ children: React.ReactNode }> = ({ children
                 fontSize: 14,
                 fontWeight: 600,
               }}>
-              A
+                {user?.name?.charAt(0)?.toUpperCase() || 'A'}
+              </div>
             </div>
           </div>
         </header>

frontend/admin-web/src/lib/api-client.ts

@@ -1,6 +1,6 @@
 import axios, { AxiosInstance, AxiosRequestConfig, AxiosResponse } from 'axios';
 
-const API_BASE_URL = process.env.NEXT_PUBLIC_API_URL || 'http://localhost:8080';
+const API_BASE_URL = process.env.NEXT_PUBLIC_API_URL || 'https://api.gogenex.com';
 
 class ApiClient {
   private client: AxiosInstance;