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

messages/zh-CN.json

@@ -133,6 +133,11 @@
     "sentencePlaceholder": "输入句子",
     "wordPlaceholder": "输入单词",
     "queryLang": "查询语言",
+    "enterLanguageName": "请输入语言名称",
+    "english": "英语",
+    "chinese": "中文",
+    "japanese": "日语",
+    "korean": "韩语",
     "meanings": "释义",
     "addMeaning": "添加释义",
     "partOfSpeech": "词性",
@@ -265,6 +270,7 @@
       "ease": "难度系数",
       "lapses": "遗忘次数",
       "showAnswer": "显示答案",
+      "nextCard": "下一张",
       "again": "重来",
       "hard": "困难",
       "good": "良好",