feat: partial locale type

app/locales/index.ts

@@ -11,6 +11,7 @@ import VI from "./vi";
 import RU from "./ru";
 import CS from "./cs";
 import KO from "./ko";
+import { merge } from "../utils/merge";
 
 export type { LocaleType } from "./cn";
 
@@ -80,7 +81,8 @@ export function changeLang(lang: Lang) {
   location.reload();
 }
 
-export default {
+const fallbackLang = EN;
+const targetLang = {
   en: EN,
   cn: CN,
   tw: TW,
@@ -95,3 +97,8 @@ export default {
   cs: CS,
   ko: KO,
 }[getLang()] as typeof CN;
+
+// if target lang missing some fields, it will use fallback lang string
+merge(fallbackLang, targetLang);
+
+export default fallbackLang as typeof CN;