feat: 初始化 uni-app 移动端项目

- cashier-mobile: 收银系统移动端（uni-app）
- customer-mobile: 顾客端移动端（uni-app）
- 包含基础页面结构：首页、订单、会员
- 更新 AGENTS.md 配置

cashier-mobile/manifest.json

@@ -0,0 +1,30 @@
+{
+  "name": "收银系统",
+  "appid": "__UNI__CASHIER001",
+  "description": "睿核科技收银系统移动端",
+  "versionName": "1.0.0",
+  "versionCode": "100",
+  "transformPx": false,
+  "app-plus": {
+    "usingComponents": true,
+    "splashscreen": {
+      "alwaysShowBeforeRender": true,
+      "waiting": true,
+      "autoclose": true,
+      "delay": 0
+    }
+  },
+  "mp-weixin": {
+    "appid": "",
+    "setting": {
+      "urlCheck": false
+    },
+    "usingComponents": true
+  },
+  "h5": {
+    "title": "收银系统",
+    "router": {
+      "mode": "hash"
+    }
+  }
+}