feat(gyeol): QuestionLayout — 질문 단계 공통 wrapper

ProgressBar + 헤더 + 본문 slot + 이전/다음 네비게이션.
nextDisabled로 validation 제어. submitting 시 버튼 비활성.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/gyeol/components/QuestionLayout.tsx

@@ -0,0 +1,74 @@
+'use client';
+
+import type { ReactNode } from 'react';
+import ProgressBar from './ProgressBar';
+import type { SurveyStep } from '@/lib/survey/types';
+import { QUESTION_HEADERS } from '@/lib/survey/questions';
+
+interface Props {
+  step: SurveyStep;
+  children: ReactNode;       // 본문 (옵션 입력 컴포넌트)
+  onPrev?: () => void;       // 이전 (없으면 미렌더)
+  onNext: () => void;        // 다음
+  nextLabel?: string;        // 기본 '다음'
+  nextDisabled?: boolean;
+  submitting?: boolean;      // Q7 전송 중 표시
+}
+
+export default function QuestionLayout({
+  step,
+  children,
+  onPrev,
+  onNext,
+  nextLabel = '다음',
+  nextDisabled = false,
+  submitting = false,
+}: Props) {
+  const header = QUESTION_HEADERS[step];
+
+  return (
+    <div className="min-h-screen flex flex-col px-6 py-8 text-white">
+      <ProgressBar step={step} />
+
+      <div className="flex-1 flex flex-col items-center justify-center max-w-md mx-auto w-full">
+        {/* 질문 헤더 */}
+        <div className="text-center mb-10 w-full">
+          <h2
+            className="kx-display text-2xl md:text-3xl font-bold mb-3 leading-snug"
+            style={{ wordBreak: 'keep-all', letterSpacing: '-0.02em' }}
+          >
+            {header?.title}
+          </h2>
+          {header?.subtitle && (
+            <p className="text-sm md:text-base text-white/60">{header.subtitle}</p>
+          )}
+        </div>
+
+        {/* 본문 */}
+        <div className="w-full mb-12">{children}</div>
+
+        {/* 네비게이션 */}
+        <div className="w-full flex gap-3">
+          {onPrev && (
+            <button
+              type="button"
+              onClick={onPrev}
+              disabled={submitting}
+              className="flex-1 py-3 rounded-full text-sm font-medium border border-white/15 text-white/60 hover:text-white hover:border-white/40 transition disabled:opacity-50"
+            >
+              ← 이전
+            </button>
+          )}
+          <button
+            type="button"
+            onClick={onNext}
+            disabled={nextDisabled || submitting}
+            className="kx-btn-primary flex-[2] py-3 rounded-full text-sm font-bold disabled:opacity-50 disabled:cursor-not-allowed"
+          >
+            {submitting ? '전송 중...' : nextLabel}
+          </button>
+        </div>
+      </div>
+    </div>
+  );
+}