新增: 多项目切换 + 业务平台 SSO 单点跳转

核心功能：
1. 多项目切换：header 新增 ProjectDropdown，切项目时自动刷新权限菜单
2. 业务平台 SSO：header 新增「业务平台」按钮，OAuth2 授权码流程无感跳转
3. SSO 回调：/sso-callback 页面接收业务平台跳回的 code，换 IoT token 登录

共享包改动：
- packages/stores：access store 新增 projectId 字段并加入持久化
- packages/effects/layouts：新增 ProjectDropdown 共享组件

apps/web-antd 改动：
- api/request.ts：
  · project-id 请求头仅在非 null 时设置（避免 axios 把 null 序列化为字符串 "null"）
  · X-Client-Id 改读 VITE_APP_CLIENT_ID，允许多个壳应用各自声明
- api/core/sso.ts：ssoCallback 参数走 body，避免 code 出现在浏览器历史/nginx 日志
- api/system/project：新增项目 simple-list API
- constants/sso.ts：集中 IOT_CLIENT_ID/BIZ_CLIENT_ID 等常量；
  generateOauthState 用 crypto.randomUUID 生成 state，替代不安全的 Math.random
- store/auth.ts：抽 completeLogin 公共收尾逻辑，新增 ssoLogin 复用
- views/_core/authentication/sso-callback.vue：SSO 回调页；
  dev 模式保留时延日志，失败时通过 query 透给登录页
- router/routes/core.ts：/sso-callback 路由 + beforeEnter 守卫
  （缺 code 直接拦回登录页，避免死循环）
- layouts/basic.vue：
  · 以 ProjectDropdown 替换 TenantDropdown（列表拉取失败兜底隐藏）
  · 切项目时调用 fetchUserInfo，避免菜单/权限陈旧
  · 新增「业务平台」跳转按钮；state 写 sessionStorage，
    生产缺 VITE_BIZ_BASE_URL 时显式报错而非静默回 localhost
  · setInterval 在 onUnmounted 中清理

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/effects/layouts/src/widgets/index.ts

@@ -8,6 +8,7 @@ export { default as AuthenticationLayoutToggle } from './layout-toggle.vue';
 export * from './lock-screen';
 export * from './notification';
 export * from './preferences';
+export * from './project-dropdown';
 export * from './tenant-dropdown';
 export * from './theme-toggle';
 export * from './timezone';

packages/effects/layouts/src/widgets/project-dropdown/index.ts

@@ -0,0 +1 @@
+export { default as ProjectDropdown } from './project-dropdown.vue';

packages/effects/layouts/src/widgets/project-dropdown/project-dropdown.vue

@@ -0,0 +1,84 @@
+<script lang="ts" setup>
+import { computed } from 'vue';
+
+import { IconifyIcon } from '@vben/icons';
+
+import {
+  Button,
+  DropdownMenu,
+  DropdownMenuContent,
+  DropdownMenuGroup,
+  DropdownMenuItem,
+  DropdownMenuTrigger,
+} from '@vben-core/shadcn-ui';
+
+interface Project {
+  id?: number;
+  name: string;
+  code?: string;
+  status?: number;
+}
+
+defineOptions({
+  name: 'ProjectDropdown',
+});
+
+const props = defineProps<{
+  projectList?: Project[];
+  visitProjectId?: null | number;
+}>();
+
+const emit = defineEmits(['success']);
+
+const projects = computed(() => props.projectList ?? []);
+
+async function handleChange(id: number | undefined) {
+  if (!id) {
+    return;
+  }
+  const project = projects.value.find((item) => item.id === id);
+  emit('success', project);
+}
+</script>
+<template>
+  <DropdownMenu>
+    <DropdownMenuTrigger>
+      <Button
+        variant="outline"
+        class="hover:bg-accent ml-1 mr-2 h-8 w-32 cursor-pointer rounded-full p-1.5"
+      >
+        <IconifyIcon icon="lucide:folder-kanban" class="mr-2" />
+        {{
+          projects.find((item) => item.id === visitProjectId)?.name ||
+          '请选择项目'
+        }}
+      </Button>
+    </DropdownMenuTrigger>
+    <DropdownMenuContent class="w-40 p-0 pb-1">
+      <DropdownMenuGroup>
+        <DropdownMenuItem
+          v-for="project in projects"
+          :key="project.id"
+          :disabled="project.id === visitProjectId"
+          class="mx-1 flex cursor-pointer items-center rounded-sm py-1 leading-8"
+          @click="handleChange(project.id)"
+        >
+          <template v-if="project.id === visitProjectId">
+            <IconifyIcon icon="lucide:check" class="mr-2" />
+            {{ project.name }}
+          </template>
+          <template v-else>
+            {{ project.name }}
+          </template>
+        </DropdownMenuItem>
+        <DropdownMenuItem
+          v-if="projects.length === 0"
+          disabled
+          class="mx-1 flex cursor-default items-center rounded-sm py-1 leading-8 text-xs opacity-60"
+        >
+          暂无项目
+        </DropdownMenuItem>
+      </DropdownMenuGroup>
+    </DropdownMenuContent>
+  </DropdownMenu>
+</template>