feat(news): add single news-item page generation and early page-ready wait

Scheduled tasks can finish once the expected HTML is on disk and stable,
instead of waiting for Goose Finish. Adds news-item templates and scripts
for generating a single-event page and committing it as a WeChat draft.

Co-authored-by: Cursor <cursoragent@cursor.com>

scheduled-task-executor.test.mjs

@@ -18,6 +18,7 @@ import {
   resendScheduledTaskWechatForReadyPage,
   resolveScheduledTaskDeliveryPollIntervalMs,
   resolveScheduledTaskDeliveryRetryDelaysMs,
+  waitForExpectedPageFile,
 } from './scheduled-task-executor.mjs';
 
 test('buildScheduledTaskExecutionPrompt includes task spec and automation marker', () => {
@@ -296,3 +297,59 @@ test('resendScheduledTaskWechatForReadyPage skips suspended users', async () =>
   assert.equal(sent, false);
   assert.equal(sendCount, 0);
 });
+
+test('waitForExpectedPageFile resolves once html file size stabilizes', async () => {
+  const root = await fs.mkdtemp(path.join(os.tmpdir(), 'scheduled-page-'));
+  const publishDir = path.join(root, 'MindSpace', 'user-1');
+  const relativePath = 'public/news-item-demo.html';
+  const filePath = path.join(publishDir, relativePath);
+  await fs.mkdir(path.dirname(filePath), { recursive: true });
+
+  let polls = 0;
+  const pending = waitForExpectedPageFile({
+    publishDir,
+    relativePath,
+    pollIntervalMs: 20,
+    stablePolls: 2,
+    minBytes: 10,
+    sleepFn: (delayMs) => new Promise((resolve) => {
+      polls += 1;
+      setTimeout(async () => {
+        if (polls === 2) {
+          await fs.writeFile(filePath, '<html>draft</html>', 'utf8');
+        }
+        resolve(delayMs);
+      }, 0);
+    }),
+  });
+
+  assert.equal(await pending, relativePath);
+});
+
+test('waitForExpectedPageFile waits until isPageReady passes', async () => {
+  const root = await fs.mkdtemp(path.join(os.tmpdir(), 'scheduled-page-ready-'));
+  const publishDir = path.join(root, 'MindSpace', 'user-2');
+  const relativePath = 'public/news-item-ready.html';
+  const filePath = path.join(publishDir, relativePath);
+  await fs.mkdir(path.dirname(filePath), { recursive: true });
+
+  let polls = 0;
+  const pending = waitForExpectedPageFile({
+    publishDir,
+    relativePath,
+    pollIntervalMs: 20,
+    stablePolls: 2,
+    minBytes: 10,
+    isPageReady: (html) => html.includes('DONE'),
+    sleepFn: (delayMs) => new Promise((resolve) => {
+      polls += 1;
+      setTimeout(async () => {
+        const body = polls >= 4 ? '<html>DONE</html>' : '<html>draft</html>';
+        await fs.writeFile(filePath, body, 'utf8');
+        resolve(delayMs);
+      }, 0);
+    }),
+  });
+
+  assert.equal(await pending, relativePath);
+});