fix(creator-studio): 固定公众号式创作工具栏

- 顶部改为 fixed 创作工具栏：左侧返回/品牌/模式，中间文章标题与保存状态，
  右侧撤销/重做、保存草稿、预览、发布
- 新增工作台级撤销/重做快照栈，连续编辑合并记录；支持 Ctrl/Cmd+Z / Shift+Z，
  不覆盖 RichText 输入框自身的编辑历史
- 移动端收敛工具栏布局，保留撤销/重做、预览、发布
- 先保存草稿再请求审核/直接发布；请求使用服务端更新后的文章与版本 ID
- 固定工具栏以独立 chrome 层布局，正文避开顶部工具栏高度
- 补充固定工具栏、历史操作与键盘快捷键契约

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

assets/creator-studio/scripts/interact.cjs

@@ -3,6 +3,7 @@
  * 并记录无法捕获的 promise 拒绝。
  */
 const fs = require('fs');
+const path = require('path');
 const puppeteer = require('puppeteer-core');
 
 const CANDIDATES = [
@@ -21,7 +22,31 @@ const URL = process.argv[2] || 'https://localhost/jio-preview.html';
     args: ['--disable-gpu', '--no-sandbox'],
   });
   const page = await browser.newPage();
-  await page.setViewport({ width: 1440, height: 1000 });
+  await page.setViewport({ width: 1440, height: 560 });
+
+  if (process.env.JIO_USE_WORKTREE_BUILD === '1') {
+    await page.setRequestInterception(true);
+    page.on('request', (request) => {
+      const pathname = new URL(request.url()).pathname;
+      const jsSuffix = '/assets/creator-studio/build/index.js';
+      const cssSuffix = '/assets/creator-studio/build/index.css';
+      if (pathname.endsWith(jsSuffix)) {
+        request.respond({
+          status: 200,
+          contentType: 'application/javascript',
+          body: fs.readFileSync(path.join(__dirname, '../build/index.js')),
+        });
+      } else if (pathname.endsWith(cssSuffix)) {
+        request.respond({
+          status: 200,
+          contentType: 'text/css',
+          body: fs.readFileSync(path.join(__dirname, '../build/index.css')),
+        });
+      } else {
+        request.continue();
+      }
+    });
+  }
 
   const errors = [];
   page.on('pageerror', (e) => errors.push('pageerror: ' + e.message));
@@ -33,8 +58,12 @@ const URL = process.argv[2] || 'https://localhost/jio-preview.html';
     blocks: document.querySelectorAll('.block-editor-block-list__block').length,
     hasInsertBtn: !!document.querySelector('.jio-creator__insert'),
     hasCover: !!document.querySelector('.jio-creator__cover'),
+    toolbarTop: document.querySelector('.jio-creator__bar')?.getBoundingClientRect().top,
   }));
-  console.log('BEFORE ' + JSON.stringify(before));
+  await page.evaluate(() => window.scrollTo(0, 700));
+  await new Promise((r) => setTimeout(r, 300));
+  const toolbarAfterScroll = await page.$eval('.jio-creator__bar', (el) => el.getBoundingClientRect().top);
+  console.log('BEFORE ' + JSON.stringify({ ...before, toolbarAfterScroll }));
 
   // 打开插入面板
   await page.click('.jio-creator__insert');