🎨 Palette: 프리셋 버튼 활성화 상태(active state) 시각 피드백 추가

[seonghobae]

💡 What

target_bytes를 빠르게 입력할 수 있도록 돕는 프리셋 버튼들("25 MiB", "100 MiB" 등)에 활성화(active) 상태 시각 피드백과 aria-pressed 접근성 속성을 추가했습니다.

🎯 Why

이전에는 프리셋 버튼을 클릭하더라도 현재 어떤 프리셋 값이 적용되어 있는지 시각적으로 알 수 없어 사용자에게 불확실성을 주었습니다. 개선 후에는 현재 입력값과 일치하는 프리셋 버튼이 동적으로 활성화(눌림 상태)되어, 사용자가 즉각적인 상태 확인을 할 수 있게 되었습니다. 직접 입력 시에도 동일하게 작동합니다.

📸 Before/After

수정된 UI에서는 입력값과 일치하는 버튼이 회색 배경과 내부 그림자(inset shadow)를 통해 시각적으로 뚜렷하게 구별됩니다.

♿ Accessibility

동적으로 업데이트되는 aria-pressed 상태를 통해 스크린 리더 사용자 또한 현재 선택된 버튼의 상태를 명확하게 알 수 있도록 접근성을 개선하였습니다.

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PR created automatically by Jules for task 18002702006988419411 started by @seonghobae

[google-labs-jules]

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[seonghobae]

Consolidating: duplicate of the already-handled Palette preset-active-state cluster (base preset buttons merged as #139; cluster keeper was #162). Closing to reduce PR sprawl — reopen if this adds something distinct.

[google-labs-jules]

Consolidating: duplicate of the already-handled Palette preset-active-state cluster (base preset buttons merged as #139; cluster keeper was #162). Closing to reduce PR sprawl — reopen if this adds something distinct.

Understood. Acknowledging that this work is a duplicate and stopping work on this task.