fix(creator-studio): 修复白屏与前台 REST 鉴权

白屏根因：CreatorRest / SubmissionVersion 位于 Jio\Core 命名空间，
但调用 Jio\Content\PrivateAssets 时缺少 use 导入，PHP 就近解析为不存在的
Jio\Core\PrivateAssets，在 wp_head 中抛致命错误导致页面输出截断。

- 为 CreatorRest、SubmissionVersion 补上 use Jio\Content\PrivateAssets
- 新增前台 api-fetch nonce 中间件：WordPress 只在后台注入 wpApiSettings，
  前台工作台里 Gutenberg core-data 请求（/wp/v2/users/me）因此全部 403
- 提交前先落一次草稿，避免自动保存未触发时发布到旧内容
- 新增 tools/check-class-refs.php：静态检测命名空间内未导入的裸类引用
- 新增 assets/creator-studio/scripts/smoke.cjs：浏览器冒烟脚本，
  抓控制台错误、失败请求与未捕获的 Promise 拒绝

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

assets/creator-studio/scripts/smoke.cjs

@@ -0,0 +1,92 @@
+/**
+ * Creator Studio 冒烟检查：用 puppeteer-core 连接本机浏览器，打开投稿页，
+ * 抓取控制台错误、失败请求与未捕获的 Promise 拒绝。
+ *
+ * 用法：
+ *   node scripts/smoke.cjs [url]
+ * 浏览器路径可用环境变量覆盖（默认按常见位置探测 Chrome / Edge）：
+ *   JIO_BROWSER="/path/to/chrome" node scripts/smoke.cjs
+ */
+const fs = require('fs');
+const puppeteer = require('puppeteer-core');
+
+const CANDIDATES = [
+  process.env.JIO_BROWSER,
+  'C:\\Program Files\\Google\\Chrome\\Application\\chrome.exe',
+  'C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe',
+  'C:\\Program Files (x86)\\Microsoft\\Edge\\Application\\msedge.exe',
+  'C:\\Program Files\\Microsoft\\Edge\\Application\\msedge.exe',
+  '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome',
+  '/usr/bin/google-chrome',
+  '/usr/bin/chromium',
+].filter(Boolean);
+
+const EDGE = CANDIDATES.find((p) => fs.existsSync(p));
+const URL = process.argv[2] || 'https://localhost/submit/';
+
+if (!EDGE) {
+  console.error('未找到可用浏览器，请设置 JIO_BROWSER 环境变量指向 Chrome/Edge 可执行文件。');
+  process.exit(1);
+}
+
+(async () => {
+  const browser = await puppeteer.launch({
+    executablePath: EDGE,
+    headless: 'new',
+    ignoreHTTPSErrors: true,
+    args: ['--disable-gpu', '--no-sandbox'],
+  });
+  const page = await browser.newPage();
+  const events = [];
+
+  page.on('console', (m) => {
+    if (m.type() === 'error' || m.type() === 'warning') {
+      events.push(`[console.${m.type()}] ${m.text()}`);
+    }
+  });
+  page.on('pageerror', (e) => {
+    events.push(`[pageerror] ${e.message}\n  stack: ${(e.stack || '').split('\n').slice(0, 6).join('\n  ')}`);
+  });
+  page.on('response', async (r) => {
+    if (r.status() >= 400) {
+      let body = '';
+      try { body = (await r.text()).slice(0, 300); } catch (_) {}
+      events.push(`[http ${r.status()}] ${r.url()}\n  body: ${body.replace(/\s+/g, ' ')}`);
+    }
+  });
+
+  await page.evaluateOnNewDocument(() => {
+    window.__jioRejections = [];
+    window.addEventListener('unhandledrejection', (e) => {
+      const r = e.reason;
+      window.__jioRejections.push(
+        r && r.status
+          ? `status=${r.status} code=${r.code || ''} msg=${r.message}`
+          : String(r && r.message ? r.message : r)
+      );
+    });
+    window.addEventListener('error', (e) => {
+      window.__jioRejections.push(`onerror: ${e.message} @ ${e.filename}:${e.lineno}`);
+    });
+  });
+
+  await page.goto(URL, { waitUntil: 'networkidle2', timeout: 60000 });
+  await new Promise((r) => setTimeout(r, 3000));
+
+  const state = await page.evaluate(() => ({
+    hasBar: !!document.querySelector('.jio-creator__bar'),
+    hasCanvas: !!document.querySelector('.jio-creator__canvas'),
+    appender: !!document.querySelector('.block-editor-default-block-appender'),
+    blocks: document.querySelectorAll('.block-editor-block-list__block').length,
+    saveText: (document.querySelector('.jio-creator__save') || {}).textContent,
+    rejections: window.__jioRejections || [],
+  }));
+  console.log('STATE ' + JSON.stringify({ ...state, rejections: undefined }));
+  if (state.rejections.length) {
+    console.log('--- rejections ---');
+    state.rejections.slice(0, 10).forEach((r) => console.log(r));
+  }
+  console.log('--- events ---');
+  events.slice(0, 30).forEach((e) => console.log(e));
+  await browser.close();
+})();