🎨 Palette: [UX/a11y improvement] Replace native disabled with aria-disabled on Save button and manage error focus

[seonghobae]

💡 What

• app.js에서 저장 버튼의 기본 disabled 속성을 제거하고 aria-disabled="true"를 사용하도록 변경했습니다.
• 입력값 검증 실패 시 포커스가 에러 메시지 컨테이너(#editor-errors)로 이동하도록 수정했습니다.

🎯 Why

• 기본 disabled 속성이 적용된 버튼은 모든 마우스 및 키보드 이벤트를 차단하기 때문에, 왜 비활성화되어 있는지를 설명하는 툴팁(title)이 사용자에게 표시되지 않는 문제가 있었습니다. aria-disabled를 사용하면 툴팁을 마우스 오버로 확인할 수 있습니다.
• 또한 제출 실패 시 스크린 리더 사용자가 오류 메시지를 즉시 확인할 수 있도록 에러 컨테이너로 포커스를 명시적으로 이동시키는 처리가 필요했습니다.

📸 Before/After

• Before: 저장 버튼 비활성화 시 마우스를 올려도 툴팁이 나타나지 않음. 폼 제출 실패 시 포커스 이동 없음.
• After: 저장 버튼 비활성화 시 마우스를 올리면 오류 설명 툴팁이 나타남. 폼 제출이 차단될 경우 오류 메시지로 포커스가 이동함.

♿ Accessibility

• 스크린 리더와 키보드 사용자 모두 비활성화된 버튼의 상태와 그 이유를 명확하게 알 수 있도록 접근성을 개선했습니다.

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PR created automatically by Jules for task 14034700740904241590 started by @seonghobae

[google-labs-jules]

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[opencode-agent]

OpenCode Review Overview

• Head SHA: 0c1ea02f04f35320098c0298ace455b88b8f525d
• Workflow run: 28744074171
• Workflow attempt: 1
• Gate result: APPROVE (exit 0)

Changed-File Evidence Map

flowchart LR
  PR["PR changed files"] --> Evidence["OpenCode bounded evidence"]
  Evidence --> S1["Changed file: app.js"]
  S1 --> I1["repository behavior"]
  I1 --> R1["Review risk: Changed file: app.js"]
  R1 --> V1["required checks"]

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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.