fix: add missing translations and fix namespace usage

- Fix srt-player to use srtT namespace for error messages
- Add deck_id.enterLanguageName and language labels (english, chinese, japanese, korean)
- Add memorize.review.nextCard translation
- Update all 8 locales with consistent translations

src/app/(features)/srt-player/page.tsx

@@ -70,7 +70,7 @@ export default function SrtPlayerPage() {
     uploadVideo((url) => {
       setVideoUrl(url);
     }, (error) => {
-      toast.error(t('videoUploadFailed') + ': ' + error.message);
+      toast.error(srtT('videoUploadFailed') + ': ' + error.message);
     });
   };
 
@@ -78,7 +78,7 @@ export default function SrtPlayerPage() {
     uploadSubtitle((url) => {
       setSubtitleUrl(url);
     }, (error) => {
-      toast.error(t('subtitleUploadFailed') + ': ' + error.message);
+      toast.error(srtT('subtitleUploadFailed') + ': ' + error.message);
     });
   };
 

src/app/decks/[deck_id]/learn/Memorize.tsx

@@ -357,7 +357,7 @@ const Memorize: React.FC<MemorizeProps> = ({ deckId, deckName }) => {
               <ChevronLeft className="w-5 h-5" />
             </LightButton>
             <span className="text-gray-500 text-sm">
-              {t("nextCard", { default: "Next" })}
+              {t("nextCard")}
               <span className="ml-2 text-xs opacity-60">Space</span>
             </span>
             <LightButton