fix(aiot): 修复摄像头保存失败 + 标题改为摄像头管理系统

- saveCamera 拆分为 addCamera/updateCamera 匹配WVP实际接口
- .env 标题改为"摄像头管理系统"
- 告警列表字段适配新三表结构
- preferences 配置调整

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

packages/@core/preferences/src/config.ts

@@ -114,7 +114,7 @@ const defaultPreferences: Preferences = {
     colorPrimary: 'hsl(212 100% 45%)',
     colorSuccess: 'hsl(144 57% 58%)',
     colorWarning: 'hsl(42 84% 61%)',
-    mode: 'dark',
+    mode: 'light',
     radius: '0.5',
     fontSize: 16,
     semiDarkHeader: false,