add properties for iOS code signing to MAUI csproj file

We need to specify the name of the Apple Distribution certificate for SIL

Author: megahirt

backend/FwLite/FwLiteMaui/FwLiteMaui.csproj

@@ -52,6 +52,10 @@
   <PropertyGroup>
     <TargetPlatform>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatform>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(TargetPlatform)' == 'ios' and '$(Configuration)' == 'Release'">
+    <CodesignKey>Apple Distribution: Summer Institute of Linguistics, Inc (SIL) (3YE4W86L3G)</CodesignKey>
+    <ArchiveOnBuild>true</ArchiveOnBuild>
+  </PropertyGroup>
   <ItemGroup>
     <!-- App Icon -->
     <!-- background color is required for mac per: https://learn.microsoft.com/en-us/dotnet/maui/user-interface/images/app-icons?view=net-maui-8.0&tabs=windows#recolor-the-background -->