Revert LangVersion to 12.0 and Roslyn to 4.11.0 to fix test failures

The LangVersion 14.0 change caused compilation issues with net8.0 and net9.0 frameworks, breaking tests. Since C# 14 implicit extensions aren't fully available yet in current Roslyn versions, keeping LangVersion at 12.0 while implementing forward-compatible code is the right approach.

Co-authored-by: PhenX <42170+PhenX@users.noreply.github.com>

Author: Copilot

Directory.Build.props

@@ -2,7 +2,7 @@
   <PropertyGroup>
 	<TargetFrameworks>net8.0;net10.0</TargetFrameworks>
 	<TreatWarningsAsErrors>true</TreatWarningsAsErrors>
-	<LangVersion>14.0</LangVersion>
+	<LangVersion>12.0</LangVersion>
 	<Nullable>enable</Nullable>
 	<EnableNETAnalyzers>true</EnableNETAnalyzers>
 	<NoWarn>CS1591</NoWarn>

Directory.Packages.props

@@ -24,8 +24,8 @@
     <PackageVersion Include="BenchmarkDotNet" Version="0.14.0" />
     <PackageVersion Include="coverlet.collector" Version="6.0.2" />
     <PackageVersion Include="Microsoft.Extensions.Logging.Console" Version="8.0.1" />
-    <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="5.0.0" />
-    <PackageVersion Include="Microsoft.CodeAnalysis.Analyzers" Version="4.14.0" />
+    <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="4.11.0" />
+    <PackageVersion Include="Microsoft.CodeAnalysis.Analyzers" Version="3.11.0" />
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
     <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
     <PackageVersion Include="ScenarioTests.XUnit" Version="1.0.1" />