docs: update Korean Book

[EatChangmyeong]

The Korean Book now contains up-to-date translation, including rewritten Error Handling and the new Auto-Cleanup chapter.

Glossary of new terms

• strictly linear: 순수 선형 (lit. purely linear)
• droppable linear: 약한 선형 (lit. weakly linear). 아핀 (affine) was indeed under consideration, but I suspect there is a reason the original text never calls it that way.
• sharable: 공유 (lit. shared) or 공유 가능 (lit. sharable). I favor the more concise 공유 for 공유 타입 (sharable type) and 공유 값 (sharable value), but fall back to 공유 가능한 if it's difficult to paraphrase that way.
• drop constraint: 정리 (lit. cleanup). I've chosen similar translation for "drop" throughout the Book, since a literal translation would be awkward.
• share constraint: 공유
• auto-cleanup: 자동 정리
• cleanup marker: 정리 표지
• * (cleanup marker syntax): 별표 (lit. asterisk)

[faiface]

Great job, thank you so much! Merging!