feat: Translate frontend/src/i18n/en.json in ko

87% of minimum 50% translated source file: 'frontend/src/i18n/en.json'
on 'ko'.

Sync of partially translated files: 
untranslated content is included with an empty translation 
or source language content depending on file format

frontend/src/i18n/ko.json

@@ -42,7 +42,8 @@
     "update": "업데이트",
     "upload": "업로드",
     "openFile": "Open file",
-    "discardChanges": "Discard"
+  "discardChanges": "Discard",
+  "saveChanges": "Save changes"
   },
   "download": {
     "downloadFile": "파일 다운로드",