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/common.ts

@@ -0,0 +1,30 @@
+
+import { CommonTranslations } from '../types/common';
+
+export const commonTranslations: CommonTranslations = {
+  welcome: "欢迎",
+  logout: "注销",
+  language: "语言",
+  english: "English",
+  khmer: "Khmer",
+  german: "Deutsch",
+  simplifiedChinese: "简体中文",
+  goodMorning: "早上好",
+  goodAfternoon: "下午好",
+  goodEvening: "晚上好",
+  profile: "个人资料",
+  settings: "设置",
+  documentation: "文档",
+  notifications: "通知",
+  close: "关闭",
+  cancel: "取消",
+  view: "查看",
+  edit: "编辑",
+  delete: "删除",
+  status: "状态",
+  time: "时间",
+  title: "标题",
+  description: "描述",
+  success: "成功",
+  error: "错误",
+};