🎨 Palette: 날짜 범위 선택기 키보드 접근성 및 상태 인지 개선

[seonghobae]

💡 What: DateRangePicker 컴포넌트의 프리셋 선택 버튼들에 명시적인 aria-pressed 상태 속성 및 키보드 focus-visible 포커스 링을 추가하였습니다.
🎯 Why: 기존 버튼 그룹은 시각적 색상으로만 상태를 구분하고 키보드 포커스 링이 빠져 있어서, 스크린 리더 등 보조 기기나 키보드 내비게이션 사용자가 현재 선택된 버튼이 무엇인지와 어떤 위치에 있는지를 명확하게 인지하기 어려웠기 때문입니다.
📸 Before/After: (Screenshot included in verification output)
♿ Accessibility: aria-pressed 속성 추가로 스크린 리더 사용자가 현재 선택된 버튼(7d, 30d 등)을 명확하게 파악할 수 있으며, focus-visible 추가로 탭(Tab) 키 이동 시 포커스 위치가 뚜렷하게 보입니다.

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PR created automatically by Jules for task 14581016327096345935 started by @seonghobae

[google-labs-jules]

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[seonghobae]

Superseded by #238: same DateRangePicker aria-pressed + focus-visible improvement, with jsdom component tests and no unrelated reformatting/config changes.

[google-labs-jules]

Superseded by #238: same DateRangePicker aria-pressed + focus-visible improvement, with jsdom component tests and no unrelated reformatting/config changes.

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