Add smart ACK provider for WeChat MP replies

Replace fixed ackText with a rule-based AckProvider that picks
response templates by message type and intent (translate, summary,
rewrite, poster, ppt, mindmap, code, search, schedule). Pure sync,
zero I/O, auto-falls back to config.ackText on any error.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

admin-server.mjs

@@ -79,6 +79,7 @@ const CONSOLES = {
         plazaPosts: services.plazaPosts,
         plazaOps: services.plazaOps,
         wechatAdmin: services.wechatAdmin,
+        subscriptionService: services.subscriptionService,
       }),
   },
   ops: {
@@ -173,6 +174,18 @@ async function main() {
 
   app.use((req, res) => res.status(404).json({ message: 'not found' }));
 
+  if (services.subscriptionService) {
+    const subExpiryTimer = setInterval(async () => {
+      try {
+        const n = await services.subscriptionService.expireStaleSubscriptions();
+        if (n > 0) console.log(`Expired ${n} stale subscription(s)`);
+      } catch (err) {
+        console.warn('Subscription expiry check failed:', err);
+      }
+    }, 60 * 60 * 1000);
+    subExpiryTimer.unref?.();
+  }
+
   app.listen(PORT, HOST, () => {
     console.log(`memind_adm @ http://${HOST}:${PORT}  (public host: ${PUBLIC_HOST})`);
     for (const { console_, allowedHosts, ipAllowlist, guarded } of summary) {