feat: sys-call framework + channel.weixin stub (v1.4.0)

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

lib/channel/weixin.js

@@ -0,0 +1,50 @@
+'use strict';
+
+/**
+ * channel.weixin — WeChat login via box-side WeChat SDK.
+ *
+ * method: login
+ *   params : { callId, timeout, emit }
+ *   returns: abort function (called on cancel)
+ *
+ * emit(msg) sends a sys-call reply back to VPS:
+ *   action:'event',    event:'qrcode',  data:{ url, expire, index }
+ *   action:'progress', event:'scanned', data:{ status:'waiting_confirm' }
+ *   action:'finish',   event:'success', data:{ wxid }
+ *   action:'finish',   event:'failed',  code, message
+ *
+ * TODO: integrate with a concrete WeChat SDK (wechaty / itchat / custom binary).
+ */
+
+const log = require('../logger');
+
+function login({ callId, timeout = 180, emit }) {
+  log.info('weixin', `login requested callId=${callId} timeout=${timeout}`);
+
+  // TODO: start WeChat SDK, get QR code, watch for scan / confirm / expire
+  // Example skeleton:
+  //
+  // const bot = startWechatyBot();
+  //
+  // bot.on('scan', (url, status) => {
+  //   emit({ action: 'event', event: 'qrcode', data: { url, expire: 30, index: ++qrIndex } });
+  // });
+  // bot.on('login', (user) => {
+  //   emit({ action: 'finish', event: 'success', data: { wxid: user.id } });
+  // });
+  // bot.on('error', (err) => {
+  //   emit({ action: 'finish', event: 'failed', code: 1001, message: err.message });
+  // });
+  // bot.start();
+  //
+  // return () => bot.stop();   // ← abort function
+
+  // Temporary stub: immediately report not implemented
+  emit({ action: 'finish', event: 'failed', code: 501, message: 'weixin SDK not implemented' });
+
+  return () => {
+    log.info('weixin', `login cancelled callId=${callId}`);
+  };
+}
+
+module.exports = { login };