feat: 파이썬 분석 엔진에 CSV 형식의 큐시트 추출 기능 추가

[seonghobae]

파이썬 분석 엔진(services/analysis-engine) 내에 곡 페이로드를 입력받아 구조화된 CSV 텍스트로 변환하는 기능을 추가했습니다.

변경 내용

• bandscope_analysis/exports/csv_export.py 모듈 신규 추가
  • build_csv_text 함수를 통해 RehearsalSong을 인메모리 버퍼 기반의 CSV 문자열로 안전하게 직렬화.
  • CSV 포뮬러 인젝션 공격 방어를 위한 선행 특수문자(=, +, -, @) 필터링 이스케이프 로직 적용.
• bandscope_analysis/exports/__init__.py의 __all__에 새 모듈 추가
• services/analysis-engine/tests/test_csv_export.py를 통한 100% 테스트 커버리지 달성
  • 성공적인 엣지 케이스, None 및 빈 매핑 구조 방어 테스트 포함.
  • 보안을 위한 인젝션 완화 메커니즘 테스트 케이스 포함.
• CHANGELOG.md 에 업데이트 내용 기록

모든 검증 스크립트(quickcheck.sh)와 pre-commit 단계를 완료하였으며, 코드 리뷰 및 메모리 기록 또한 반영되었습니다.

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PR created automatically by Jules for task 11423156772664678875 started by @seonghobae

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[Copilot]

Pull request overview

Adds a CSV cue-sheet export path to the Python analysis engine (services/analysis-engine) so a RehearsalSong-shaped payload can be serialized into a structured CSV text output suitable for downstream use (e.g., cue sheets), with explicit formula-injection mitigation and test coverage.

Changes:

• Introduces build_csv_text() in a new bandscope_analysis.exports.csv_export module to emit an in-memory CSV string from cue-sheet rows, including CSV formula-injection escaping.
• Exposes the new export via bandscope_analysis.exports package exports.
• Adds a dedicated test suite covering success cases, malformed input behavior, and injection mitigation; updates CHANGELOG.md.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
services/analysis-engine/src/bandscope_analysis/exports/csv_export.py	New CSV export builder with formula-injection escaping and safe handling of malformed/empty input.
services/analysis-engine/src/bandscope_analysis/exports/init.py	Re-exports build_csv_text via the exports package surface.
services/analysis-engine/tests/test_csv_export.py	Adds tests for CSV output shape, edge cases, and injection mitigation behavior.
CHANGELOG.md	Documents the new CSV cue-sheet export feature.

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.