feat(translations): Add Simplified Chinese translation

- Add simplified Chinese translation files
- Add the Simplified Chinese option in the language selection
- Update the translation index to support Simplified Chinese

application/src/translations/zhcn/settings.ts

@@ -0,0 +1,52 @@
+
+import { SettingsTranslations } from '../types/settings';
+
+export const settingsTranslations: SettingsTranslations = {
+  // Tabs
+  systemSettings: "系统设置",
+  mailSettings: "邮件设置",
+  
+  // System Settings
+  appName: "应用名称",
+  appURL: "应用 URL",
+  senderName: "发送者名称",
+  senderEmail: "发送者邮箱地址",
+  hideControls: "隐藏控件",
+  
+  // Mail Settings
+  smtpSettings: "SMTP 配置",
+  smtpEnabled: "启用 SMTP",
+  smtpHost: "SMTP 主机",
+  smtpPort: "SMTP 端口",
+  smtpUsername: "SMTP 用户名",
+  smtpPassword: "SMTP 密码",
+  smtpAuthMethod: "认证方法",
+  enableTLS: "启用 TLS",
+  localName: "本地名称",
+  
+  // Test Email
+  testEmail: "测试邮箱",
+  sendTestEmail: "发送测试邮箱",
+  emailTemplate: "邮箱模板",
+  verification: "验证",
+  passwordReset: "密码重置",
+  confirmEmailChange: "确认邮箱变更",
+  otp: "OTP",
+  loginAlert: "登录警报",
+  authCollection: "认证集合",
+  selectCollection: "选择集合",
+  toEmailAddress: "收件人邮箱地址",
+  enterEmailAddress: "输入收件人邮箱地址",
+  sending: "发送中...",
+  
+  // Actions and status
+  save: "保存变更",
+  saving: "保存中...",
+  settingsUpdated: "设置已成功更新",
+  errorSavingSettings: "保存设置时出错",
+  errorFetchingSettings: "加载设置时出错",
+  testConnection: "测试连接",
+  testingConnection: "测试连接中...",
+  connectionSuccess: "连接成功",
+  connectionFailed: "连接失败"
+};