feat(wechat): add Intent Transaction Layer with unified task schema

Introduce Draft → Confirm → Commit flow for WeChat schedule intents behind
feature flags, plus h5_tasks dual-write/read aggregation and rollout scripts
so reminders and automations get explicit user confirmation before persisting.

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

scripts/verify-schedule-reminder-create.mjs

@@ -184,19 +184,40 @@ async function testWechatHandlerIsolation() {
   }
 
   const agentReply = await handleWechatScheduleIntent({
-    intent: { agentText: '今天10点提醒我吃药', msgId: 'msg-agent' },
+    intent: { agentText: '明天早上六点去跑步，五点半提醒我', msgId: 'msg-agent' },
     user: { userId: 'user-1' },
     scheduleService,
   });
   if (agentReply === null) {
-    pass('服务号一次性提醒', '仍 fall through 给 Agent（schedule_agent）');
+    pass('服务号复杂提醒', '仍 fall through 给 Agent（多时间点）');
   } else {
-    fail('服务号一次性提醒', `expected null, got ${agentReply}`);
+    fail('服务号复杂提醒', `expected null, got ${agentReply}`);
+  }
+
+  const directReply = await handleWechatScheduleIntent({
+    intent: { agentText: '今天10点提醒我吃药', msgId: 'msg-direct' },
+    user: { userId: 'user-1' },
+    scheduleService: {
+      ...scheduleService,
+      async createItem(payload) {
+        calls.push(['createItem', payload.title]);
+        return { id: 'item-direct', ...payload };
+      },
+      async createReminder(payload) {
+        calls.push(['createReminder', payload.itemId]);
+        return { id: 'reminder-direct', ...payload };
+      },
+    },
+  });
+  if (directReply?.includes('已设置提醒') && calls.some((entry) => entry[0] === 'createReminder')) {
+    pass('服务号简单提醒', '规则路径直接 createItem + createReminder');
+  } else {
+    fail('服务号简单提醒', JSON.stringify({ directReply, calls }));
   }
 
   const intent = parseScheduleIntent('今天10点提醒我吃药');
-  if (shouldUseScheduleAssistant('今天10点提醒我吃药')) {
-    pass('意图路由', `一次性提醒走 Agent 路径（parseScheduleIntent=${intent.action}，由 prompt 加载 schedule-assistant）`);
+  if (intent.action === 'create_timed_reminder') {
+    pass('意图路由', '简单一次性提醒走规则 preflight（create_timed_reminder）');
   } else {
     fail('意图路由', JSON.stringify(intent));
   }