[l10n] Complete translations (#3794)

**Short description**: I completed the translations with the help of
translation tools.

**Long description**: I'm currently looking at the translation-tests and
I noticed the e2e-test `${language} should contain all base keys, ()`.
It is supposed to check whether all keys are present in each translation
file, but it doesn't actually work that way. When I fix it, a lot of
missing translations are reported. I have completed these translations
with the help of translation tools and packed them into this PR. I have
left out the modified test so that we can focus on the question if we
accept such amount of automatic translations or not.

rejas has already expressed in another PR
(https://github.com/MagicMirrorOrg/MagicMirror/pull/3775#discussion_r2083099252)
that he prefers human translators. I basically do too, but I don't see
how we can manage to have all translations completed by humans. And even
if a few translations are not correct, hopefully a user will get in
touch.

If we decide against the translations, we should at least remove the
test. If we go for the tranlsations, I'll add the test.

What do you think?

---------

Co-authored-by: Magnus <34011212+MagMar94@users.noreply.github.com>

translations/ko.json

@@ -1,6 +1,7 @@
 {
 	"LOADING": "로드 중 …",
 
+	"DAYBEFOREYESTERDAY": "그저께",
 	"YESTERDAY": "어제",
 	"TODAY": "오늘",
 	"TOMORROW": "내일",
@@ -27,7 +28,8 @@
 	"NNW": "북북서풍",
 
 	"FEELS": "체감온도 {DEGREE}",
-	"PRECIP_POP": "PoP",
+	"PRECIP_POP": "강수 확률",
+	"PRECIP_AMOUNT": "강수량",
 
 	"MODULE_CONFIG_CHANGED": "모듈 {MODULE_NAME}의 설정값이 바뀌었습니다.\n매뉴얼을 참고하세요.",
 	"MODULE_CONFIG_ERROR": "에러 : {MODULE_NAME} - {ERROR}",
@@ -36,8 +38,13 @@
 	"MODULE_ERROR_UNAUTHORIZED": "인증이 실패했습니다.",
 	"MODULE_ERROR_UNSPECIFIED": "상세 내용은 로그를 확인하세요.",
 
+	"NEWSFEED_NO_ITEMS": "현재 뉴스가 없습니다.",
+
 	"UPDATE_NOTIFICATION": "새로운 MagicMirror² 업데이트가 있습니다.",
 	"UPDATE_NOTIFICATION_MODULE": "{MODULE_NAME} 모듈에서 사용 가능한 업데이트 입니다.",
 	"UPDATE_INFO_SINGLE": "설치할 {COMMIT_COUNT} commit 는 {BRANCH_NAME} 분기에 해당됩니다.",
-	"UPDATE_INFO_MULTIPLE": "설치할 {COMMIT_COUNT} commits 는 {BRANCH_NAME} 분기에 해당됩니다."
+	"UPDATE_INFO_MULTIPLE": "설치할 {COMMIT_COUNT} commits 는 {BRANCH_NAME} 분기에 해당됩니다.",
+	"UPDATE_NOTIFICATION_DONE": "모듈 {MODULE_NAME}의 업데이트가 완료되었습니다.",
+	"UPDATE_NOTIFICATION_ERROR": "모듈 {MODULE_NAME}의 업데이트 중 오류가 발생했습니다.",
+	"UPDATE_NOTIFICATION_NEED-RESTART": "MagicMirror를 재시작해야 합니다."
 }