🎨 Palette: 프로젝트 뷰 모드 토글의 키보드 접근성 및 탭 시맨틱 개선

[seonghobae]

💡 What: 프로젝트 레이아웃의 뷰 모드(프로젝트 상세, 마일스톤, 의사결정 로그) 토글 버튼을 시맨틱 탭(role="tab")으로 변경하고, 키보드 네비게이션 시 포커스 상태를 명확히 보여주는 focus-visible 유틸리티를 추가했습니다.
🎯 Why: 기존 뷰 모드 토글은 단순 버튼 역할만 수행하여 스크린 리더 환경이나 키보드 네비게이션 환경에서 탭이 전환되는 형태라는 시맨틱 정보를 제대로 전달하지 못하고 활성 상태 및 포커스 시각적 피드백이 부족했습니다.
♿ Accessibility:

• 컨테이너에 role="tablist"와 aria-label을 추가
• 토글 버튼에 role="tab"과 aria-selected를 활용해 명시적인 탭 구조 선언
• focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/40 클래스를 추가해 키보드 이용자의 초점 이동 확인 편의성 제공

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PR created automatically by Jules for task 13851726164629355335 started by @seonghobae

[google-labs-jules]

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[seonghobae]

Closing during org-wide PR backlog reduction. This looks like a low-priority automated maintenance PR (palette ux/a11y), while the repository has a large backlog of security, conflict, and required-workflow work. Reopen or recreate a fresh PR if this change is still needed.

[google-labs-jules]

Closing during org-wide PR backlog reduction. This looks like a low-priority automated maintenance PR (palette ux/a11y), while the repository has a large backlog of security, conflict, and required-workflow work. Reopen or recreate a fresh PR if this change is still needed.

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