optimized and add diagnostic feature

Billing.Shared/Billing.Shared.projitems

@@ -85,6 +85,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)SplashPage.xaml.cs">
       <DependentUpon>SplashPage.xaml</DependentUpon>
     </Compile>
+    <Compile Include="$(MSBuildThisFileDirectory)Models\Logs.cs" />
   </ItemGroup>
   <ItemGroup>
     <EmbeddedResource Include="$(MSBuildThisFileDirectory)MainShell.xaml">