Add 卓米会 mini program and admin server.

Initial commit of the WeChat mini program, Express backend, and admin console.

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

miniprogram/utils/media.js

@@ -0,0 +1,9 @@
+const config = require('../config')
+
+function absUrl(url) {
+  if (!url) return ''
+  if (/^https?:\/\//.test(url)) return url
+  return config.BASE + url
+}
+
+module.exports = { absUrl: absUrl }