fix: defult language

src/utils/language.ts

@@ -0,0 +1,42 @@
+import type { Language } from '@/types';
+import { STORAGE_KEY_LANGUAGE } from '@/utils/constants';
+
+const parseStoredLanguage = (value: string): Language | null => {
+  try {
+    const parsed = JSON.parse(value);
+    const candidate = parsed?.state?.language ?? parsed?.language ?? parsed;
+    if (candidate === 'zh-CN' || candidate === 'en') {
+      return candidate;
+    }
+  } catch {
+    if (value === 'zh-CN' || value === 'en') {
+      return value;
+    }
+  }
+  return null;
+};
+
+const getStoredLanguage = (): Language | null => {
+  if (typeof window === 'undefined') {
+    return null;
+  }
+  try {
+    const stored = localStorage.getItem(STORAGE_KEY_LANGUAGE);
+    if (!stored) {
+      return null;
+    }
+    return parseStoredLanguage(stored);
+  } catch {
+    return null;
+  }
+};
+
+const getBrowserLanguage = (): Language => {
+  if (typeof navigator === 'undefined') {
+    return 'zh-CN';
+  }
+  const raw = navigator.languages?.[0] || navigator.language || 'zh-CN';
+  return raw.toLowerCase().startsWith('zh') ? 'zh-CN' : 'en';
+};
+
+export const getInitialLanguage = (): Language => getStoredLanguage() ?? getBrowserLanguage();