feat: CLAUDE.md 파일을 수정하다

- 영어로 답변해서 조금 힘들어 한국어로 답변할 수 있도록 추가함.

Author: ujuc

CLAUDE.md

@@ -3,6 +3,11 @@
 This file provides guidance to Claude Code (claude.ai/code) when working with
 code in this repository.
 
+## Language
+
+**IMPORTANT: Always respond in Korean (한국어) when working with this codebase,
+as this is a Korean personal blog.**
+
 ## Project Overview
 
 This is a Korean personal blog powered by Pelican (static site generator) with a