fix(frontend): keep browser API on same-origin rewrites in dev

Document that NEXT_PUBLIC_WAVELET_BACKEND_URL must stay unset for local
next dev so axios hits /api/* and Next rewrites proxy to the backend.

frontend/components/common/file-image-preview.tsx

@@ -5,6 +5,7 @@ import { ImageOff } from 'lucide-react';
 
 import { cn } from '@/lib/utils';
 import { getFileUrl, type ImageQuality } from '@/lib/services/upload/utils';
+import { useTranslations } from 'next-intl';
 
 type FileImagePreviewProps = {
   fileId: string | number;
@@ -25,6 +26,7 @@ export function FileImagePreview({
 }: FileImagePreviewProps) {
   const [failed, setFailed] = React.useState(false);
   const src = getFileUrl(fileId, quality);
+  const t = useTranslations('common');
 
   React.useEffect(() => {
     setFailed(false);
@@ -34,7 +36,7 @@ export function FileImagePreview({
     return (
       <div
         role='img'
-        aria-label={`${alt} 加载失败`}
+        aria-label={`${alt} ${t('loadFailed')}`}
         className={cn(
           'flex size-full flex-col items-center justify-center gap-1 bg-muted/50 text-muted-foreground',
           fallbackClassName,
@@ -47,7 +49,7 @@ export function FileImagePreview({
           )}
         />
         {variant === 'default' && (
-          <span className='text-[10px] leading-none'>加载失败</span>
+          <span className='text-[10px] leading-none'>{t('loadFailed')}</span>
         )}
       </div>
     );