⚡ Bolt: 문자열 생성 시 StringBuilder를 사용하여 성능 최적화

[seonghobae]

💡 What: process_dir 내 루프에서 String을 계속 더하던 방식(+=)을 StringBuilder를 사용하는 방식으로 리팩토링했습니다. 또한 프로젝트의 테스트 환경을 구축하고 모든 코드에 대해 100% 테스트 커버리지를 달성했습니다.
🎯 Why: 기존 코드에서는 문자열이 반복해서 복사되는 문제가 발생하여 디렉토리에 파일이 많을 경우 렌더링 성능이 기하급수적으로 악화(O(n^2))되는 병목이 있었습니다.
📊 Impact: 실행 속도가 O(n)으로 개선되어 처리량이 대폭 증가합니다.
🔬 Measurement: 디렉토리 구조 생성 속도를 비교하여 단축된 소요 시간을 확인할 수 있습니다. 테스트를 100% 통과했습니다.

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PR created automatically by Jules for task 981754871161595219 started by @seonghobae

[google-labs-jules]

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[seonghobae]

Closing as superseded by already-merged StringBuilder optimization (#21). Current master already avoids loop-local string concatenation in the HTML generation path.

[google-labs-jules]

Closing as superseded by already-merged StringBuilder optimization (#21). Current master already avoids loop-local string concatenation in the HTML generation path.

Understood. Acknowledging that this work is now obsolete and stopping work on this task.