Add permission checks and localization improvements

- Add grant check (64, 'X') to QNA register page
- Add grant check (45, 'X') to user login auth modification
- Replace hardcoded Korean permission messages with i18n key 'common.nopermission'
- Add 'nopermission' translation key to both en.json and ko.json
- Update .env.development to use development API endpoints

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/locales/ko.json

@@ -15,6 +15,7 @@
         "error": "오류가 발생했습니다",
         "success": "성공",
         "noData": "데이터가 없습니다",
+        "nopermission": "권한이 없습니다",
         "next": "다음",
         "latest": "최신순",
         "oldest": "오래된순",