🛡️ Sentinel: [MEDIUM] 전역 보안 헤더 적용 (HSTS 및 nosniff)

[seonghobae]

전역적인 애플리케이션 보안 강화를 위해, X-Content-Type-Options: nosniff 및 Strict-Transport-Security (HSTS) 헤더를 모든 HTTP 응답에 적용하도록 ViewerSecurityHeadersWebFilter를 개선했습니다. 아울러 발견된 취약점과 대응 방안을 .jules/sentinel.md 파일에 기록했습니다.

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PR created automatically by Jules for task 17788313081949524363 started by @seonghobae

[google-labs-jules]

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[seonghobae]

중복 정리(2차): '전역 보안 헤더(HSTS/nosniff)' 클러스터 중복 → 정본 #56 유지. 동일 목적/파일로 동시 병합 불가. 고유 변경은 #56에 반영하거나 재오픈.

[google-labs-jules]

중복 정리(2차): '전역 보안 헤더(HSTS/nosniff)' 클러스터 중복 → 정본 #56 유지. 동일 목적/파일로 동시 병합 불가. 고유 변경은 #56에 반영하거나 재오픈.

알겠습니다. 정본 #56이 유지됨을 확인하였으며, 이 PR이 중복으로 간주됨에 따라 작업을 중단하겠습니다.