feat: enhance project configurations for improved debugging and packaging

- Marked `LocalPortFilteringDemo` project as non-packable to exclude it from NuGet packaging.
- Updated `LocalPortFiltering.AspNetCore` project:
  - Enabled symbol package generation (`snupkg`) for better debugging.
  - Embedded untracked sources to improve debugging experience.
  - Published repository URL for source control integration.
  - Added `Microsoft.SourceLink.GitHub` for enhanced source linking in debugging.

Author: willysoft

sample/LocalPortFilteringDemo/LocalPortFilteringDemo.csproj

@@ -4,6 +4,7 @@
     <TargetFramework>net8.0</TargetFramework>
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
+    <IsPackable>false</IsPackable>
   </PropertyGroup>
 
   <ItemGroup>

src/LocalPortFiltering.AspNetCore/LocalPortFiltering.AspNetCore.csproj

@@ -23,10 +23,15 @@
     <IsPackable>true</IsPackable>
     <PackageReadmeFile>README.md</PackageReadmeFile>
     <PackageLicenseFile>LICENSE</PackageLicenseFile>
+    <IncludeSymbols>true</IncludeSymbols>
+    <SymbolPackageFormat>snupkg</SymbolPackageFormat>
+    <EmbedUntrackedSources>true</EmbedUntrackedSources>
+    <PublishRepositoryUrl>true</PublishRepositoryUrl>
   </PropertyGroup>
 
   <ItemGroup>
     <FrameworkReference Include="Microsoft.AspNetCore.App" />
+    <PackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" PrivateAssets="All"/>
   </ItemGroup>
 
   <ItemGroup>