fix: defer mini program phone auth until login

miniprogram/pages/web-view/index.wxml

@@ -1,5 +1,6 @@
 <block wx:if="{{webViewUrl}}">
   <web-view
+    id="genarrative-web-view"
     src="{{webViewUrl}}"
     bindload="handleWebViewLoad"
     binderror="handleWebViewError"
@@ -19,6 +20,9 @@
     <view wx:if="{{errorMessage}}" class="setup-text setup-text--danger">
       {{errorMessage}}
     </view>
+    <view wx:if="{{returnToPreviousPage}}" class="setup-text">
+      登录完成后将自动返回。
+    </view>
     <button
       class="retry-button"
       open-type="getPhoneNumber"