refactor(frontend): modify i18n korean translatiion

[shing100]

Updated the Korean translation for the key "en" in the section where OpenDevin introduces itself, to make it more specific and localized. The previous text was a direct English transliteration, while the new text translates and adapts the message for Korean speakers. Changed the translation for "Assistant" in Korean from the English word "Assistant" to the Korean word "어시스턴트", which is a transliteration of the English term into Korean script.

[rbren]

So cool to see that!