fix(i18n-ko): unify 2FA terminology, add notConnected/endpoint/endpointDesc, keep PreUp
Added translation using Weblate (Korean) Translate-URL: https://mini-i18n.daeho.ro/projects/wg-easy/main/ko/ Translation: wg-easy/main Co-authored-by: OpenAI <noreply-mt-openai@weblate.org>