feat: redesign homepage as dashboard workspace

Replace simple welcome message with functional dashboard including greeting and quick action cards.

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

src/pages/index.tsx

@@ -1,3 +1,92 @@
-export default function index() {
+import React from 'react';
-  return <div>欢迎登录</div>;
+import { useMyState } from '@/common';
+import {
+  BuildingOutlined,
+  ImportOutlined,
+  TeamOutlined,
+} from '@ant-design/icons';
+import QuickActionCard from './components/QuickActionCard';
+
+export default function Index() {
+  const { snap } = useMyState();
+  const username = snap.session?.user?.username || '用户';
+
+  const quickActions = [
+    {
+      icon: <BuildingOutlined />,
+      title: '添加机构',
+      description: '快速创建新的机构',
+      themeColor: '#1890ff',
+      path: '/company/list',
+    },
+    {
+      icon: <ImportOutlined />,
+      title: '导入项目',
+      description: '批量导入项目数据',
+      themeColor: '#52c41a',
+      path: '/asset/list',
+    },
+    {
+      icon: <TeamOutlined />,
+      title: '导入员工',
+      description: '批量导入员工数据',
+      themeColor: '#fa8c16',
+      path: '/company/employees',
+    },
+  ];
+
+  return (
+    <div style={{
+      padding: '48px 24px',
+      minHeight: 'calc(100vh - 64px)',
+      background: '#f0f2f5',
+    }}>
+      <div style={{
+        maxWidth: 1200,
+        margin: '0 auto',
+      }}>
+        {/* 欢迎语区域 */}
+        <div style={{
+          marginBottom: 48,
+          textAlign: 'center',
+        }}>
+          <h1 style={{
+            fontSize: 32,
+            fontWeight: 600,
+            color: '#262626',
+            marginBottom: 12,
+          }}>
+            欢迎回来，{username}！
+          </h1>
+          <p style={{
+            fontSize: 16,
+            color: '#8c8c8c',
+            marginBottom: 0,
+          }}>
+            这里是您的快捷工作台，点击下方卡片快速开始常用操作
+          </p>
+        </div>
+
+        {/* 快捷操作卡片区域 */}
+        <div style={{
+          display: 'grid',
+          gridTemplateColumns: 'repeat(auto-fit, minmax(280px, 1fr))',
+          gap: 24,
+          maxWidth: 900,
+          margin: '0 auto',
+        }}>
+          {quickActions.map((action) => (
+            <QuickActionCard
+              key={action.path}
+              icon={action.icon}
+              title={action.title}
+              description={action.description}
+              themeColor={action.themeColor}
+              to={action.path}
+            />
+          ))}
+        </div>
+      </div>
+    </div>
+  );
 }