🛡️ Sentinel: [MEDIUM] Fix runtime error information leakage in stem separation worker

[seonghobae]

🚨 Severity: MEDIUM
💡 Vulnerability: bandscope_analysis.api 모듈의 _stem_separation_worker에서 발생한 예외를 처리할 때, str(error)를 그대로 사용자에게 반환하여 내부 스택 트레이스나 파일 시스템 경로 같은 민감한 정보가 노출될 수 있는 위험이 있었습니다.
🎯 Impact: 악의적인 사용자가 이러한 에러 메시지를 통해 내부 시스템 구조와 경로 정보를 수집하여 다른 공격에 활용할 수 있습니다.
🔧 Fix: 예상치 못한 포괄적 Exception이 발생할 경우 예외 객체의 메시지를 노출하지 않고, "An unexpected error occurred during stem separation."과 같은 정적인 일반 에러 메시지를 반환하도록 수정했습니다.
✅ Verification: 테스트 코드 test_stem_separation_worker_maps_safe_error_kinds를 업데이트하여 이 수정 사항이 예상대로 동작하는지 확인하였고 전체 테스트를 통과했습니다.

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PR created automatically by Jules for task 3480032664147161573 started by @seonghobae

[google-labs-jules]

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[seonghobae]

Superseded by #497. The replacement keeps the same analysis-engine error information-leak mitigation and includes the follow-up fixes for stale reviewer findings.

[seonghobae]

Closing as superseded by #497.

[google-labs-jules]

Superseded by #497. The replacement keeps the same analysis-engine error information-leak mitigation and includes the follow-up fixes for stale reviewer findings.

Understood. Acknowledging that this work is superseded by #497 and stopping work on this task.

[google-labs-jules]

Closing as superseded by #497.

Understood. Acknowledging that this PR is being closed and superseded by #497.