Lower C# WinML target framework

Align the C# SDK WinML package and test project target frameworks with the WinML GA minimum Windows version.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: bmehta001

sdk/cs/src/Microsoft.AI.Foundry.Local.csproj

@@ -88,7 +88,7 @@
       <PackageId>Microsoft.AI.Foundry.Local.WinML</PackageId>
       <AssemblyName>Microsoft.AI.Foundry.Local.WinML</AssemblyName>
       <DefineConstants>$(DefineConstants);IS_WINML</DefineConstants>
-      <TargetFramework>net9.0-windows10.0.26100.0</TargetFramework> <!-- override -->
+      <TargetFramework>net9.0-windows10.0.18362.0</TargetFramework> <!-- override -->
       <RuntimeIdentifiers>win-x64;win-arm64</RuntimeIdentifiers>
       <TargetPlatformMinVersion>10.0.18362.0</TargetPlatformMinVersion>
 

sdk/cs/test/FoundryLocal.Tests/Microsoft.AI.Foundry.Local.Tests.csproj

@@ -19,7 +19,7 @@
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(UseWinML)'=='true'">
-    <TargetFramework>net9.0-windows10.0.26100.0</TargetFramework>
+    <TargetFramework>net9.0-windows10.0.18362.0</TargetFramework>
     <TargetPlatformMinVersion>10.0.18362.0</TargetPlatformMinVersion>
     <WindowsPackageType>None</WindowsPackageType>
   </PropertyGroup>