feat(contract-manage): 将合同详情由弹窗改为独立页面

- 新增路由 /business/contract-manage/detail，详情页共享合同管理组件
- 列表、表单、详情三分支用 isFormPage 和 isDetailPage 控制
- openDetail 方法改为跳转详情路由，initDetailPage 获取详情数据
- 新增 resetDetailState 和 closeDetailPage 方法，复用关闭逻辑
- 详情页去除弹窗高度限制，样式改为页面自滚动
- 详情页底栏使用固定位置关闭按钮，保持页面布局一致
- watch 和 created 中添加对 isDetailPage 的初始化调用和监听

src/router/views/index.js

@@ -287,6 +287,18 @@ export default [
       },
     ],
   },
+  {
+    path: '/business/contract-manage/detail',
+    component: Layout,
+    children: [
+      {
+        path: '',
+        name: '合同详情',
+        meta: { keepAlive: false, activeMenu: '/business/contract-manage' },
+        component: () => import('@/views/business/contract-manage.vue'),
+      },
+    ],
+  },
   {
     path: '/business/contract-manage/change',
     component: Layout,