perf: move van-icon component to app env

app.json

@@ -1,11 +1,15 @@
 {
-  "entryPagePath": "pages/index/index",
+  "entryPagePath": "pages/permisission/permission",
   "pages": [
     "pages/permisission/permission",
     "pages/index/index",
     "pages/report/report",
-    "pages/my/my"
+    "pages/my/my",
+    "pages/buy/buy"
   ],
+  "usingComponents": {
+    "van-icon": "@vant/weapp/icon/index"
+  },
   "window": {
     "backgroundTextStyle": "light",
     "navigationBarBackgroundColor": "#45A6B5",

pages/index/index.json

@@ -1,7 +1,6 @@
 {
   "navigationBarTitleText": "首页",
   "usingComponents": {
-    "van-button": "@vant/weapp/button/index",
-    "van-icon": "@vant/weapp/icon/index"
+    "van-button": "@vant/weapp/button/index"
   }
 }