feat(wysiwyg): 레이어/속성 패널 및 Export(절대배치) 1차 TDD/구현

- LayersPanel: 순서 변경/잠금/숨김 토글
- PropsPanel: 위치/크기/회전 및 이미지 src/alt 편집
- exportFrame: frame-scale 토큰 및 오브젝트 절대배치 HTML/CSS 출력
- 테스트 추가 및 전체 그린 유지

lib/wysiwyg/export.ts

@@ -0,0 +1,48 @@
+import type { Frame, WObject } from '@/lib/wysiwyg/schema'
+
+export type Exported = { html: string; css: string; js: string }
+
+function esc(s: string) {
+  return s.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;')
+}
+
+function isImage(o: WObject): o is Extract<WObject, { type: 'image' }> { return o.type === 'image' }
+function isText(o: WObject): o is Extract<WObject, { type: 'text' }> { return o.type === 'text' }
+function isButton(o: WObject): o is Extract<WObject, { type: 'button' }> { return o.type === 'button' }
+
+function renderObject(o: WObject): { html: string; css: string } {
+  const baseCss = `#${o.id}{position:absolute;left:${o.x}px;top:${o.y}px;width:${o.width}px;height:${o.height}px;transform:rotate(${o.rotate}deg)}`
+  if (isImage(o)) {
+    const html = `<img id="${o.id}" src="${esc(o.props.src)}" alt="${esc(o.props.alt || '')}" />`
+    return { html, css: baseCss }
+  }
+  if (isText(o)) {
+    const html = `<p id="${o.id}">${esc(o.props.text)}</p>`
+    return { html, css: baseCss + `;font-size:${o.props.fontSize}px;color:${o.props.color}` }
+  }
+  // button minimal
+  const label = isButton(o) ? o.props.label : 'Button'
+  const href = isButton(o) ? (o.props.href || '#') : '#'
+  const html = `<a id="${o.id}" href="${esc(href)}">${esc(label)}</a>`
+  return { html, css: baseCss }
+}
+
+export function exportFrame(frame: Frame): Exported {
+  const piecesHtml: string[] = []
+  const piecesCss: string[] = []
+  for (const layer of frame.layers) {
+    if (!layer.visible) continue
+    for (const o of layer.objects) {
+      const r = renderObject(o)
+      piecesHtml.push(r.html)
+      piecesCss.push(r.css)
+    }
+  }
+  const html = `<div class="frame-scale"><div class="frame">${piecesHtml.join('')}</div></div>`
+  const css = [
+    `.frame{position:relative;width:${frame.width}px;height:${frame.height}px;background:${frame.background}}`,
+    `.frame-scale{transform-origin:0 0}`,
+    ...piecesCss,
+  ].join('\n')
+  return { html, css, js: '' }
+}