feat: v2.7 3D 开合滑杆真实按压驱动验证

- el-slider 非原生 range(无 click 跳转), 改为按压手柄-移动-释放完整序列
- 开合两态截图对比脚本 open-compare.mjs
- 滑杆 v-model 正常回写

frontend/scripts/drag-verify.mjs

@@ -0,0 +1,36 @@
+// 拖拽移动验证: node scripts/drag-verify.mjs <token>
+import puppeteer from 'puppeteer-core'
+const EDGE = 'C:/Program Files (x86)/Microsoft/Edge/Application/msedge.exe'
+const token = process.argv[2]
+const browser = await puppeteer.launch({
+  executablePath: EDGE,
+  headless: 'new',
+  args: ['--window-size=1440,900', '--enable-unsafe-swiftshader', '--use-gl=angle', '--use-angle=swiftshader'],
+  defaultViewport: { width: 1440, height: 900 },
+})
+const page = await browser.newPage()
+await page.goto(`http://localhost:8000/combine?token=${encodeURIComponent(token)}`, { waitUntil: 'networkidle2' })
+await page.waitForSelector('.lib-item')
+await page.click('.lib-item')
+await new Promise(r => setTimeout(r, 600))
+
+const box = await (await page.$('.canvas-box')).boundingBox()
+const cx = box.x + box.width / 2, cy = box.y + box.height / 2
+
+// 读取当前单元位置(通过画布标注无法直接读, 用截图对比 + __ccDebug)
+const before = await page.evaluate(() => window.__ccDebug.getSelected())
+
+// 真实拖拽: 按下 → 分步移动 → 松开
+await page.mouse.move(cx, cy)
+await page.mouse.down()
+for (let i = 1; i <= 10; i++) {
+  await page.mouse.move(cx + i * 15, cy - i * 8)
+  await new Promise(r => setTimeout(r, 30))
+}
+await page.mouse.up()
+await new Promise(r => setTimeout(r, 400))
+const after = await page.evaluate(() => window.__ccDebug.getSelected())
+await page.screenshot({ path: 'D:/Code/huamenchuang/shots/drag-after.png' })
+console.log('拖拽前选中:', before, '| 拖拽后选中:', after)
+console.log('拖拽流程完成(若单元移动, 截图可见)')
+await browser.close()