Migrate all WebApp projects to .NET 10

[Copilot]

Updates all C# projects from .NET 8 to .NET 10 target framework with compatible package versions.

Changes

Project Files

• Microsoft.SPID.Proxy.csproj: net8.0 → net10.0
• CNS.Auth.Web.csproj: net8.0 → net10.0

Package Updates

Microsoft.SPID.Proxy:

• Azure.Identity: 1.11.0 → 1.13.1 (resolves CVE GHSA-m5vv-6r4h-3vj9)
• Azure.Extensions.AspNetCore.Configuration.Secrets: 1.3.1 → 1.3.2
• ASP.NET Core packages: 8.0.x → 10.0.0
• System.Management, System.Runtime.Caching: 8.0.0 → 10.0.0

CNS.Auth.Web:

• ASP.NET Core packages: 8.0.x → 10.0.0
• Microsoft.IdentityModel.Tokens.Saml: 6.14.0 → 8.3.1

Notes

Deprecation warnings introduced (SYSLIB0057, ASPDEPR005, SYSLIB0028) are expected for .NET 10. These APIs remain functional but should be migrated to recommended alternatives in future work:

• X509Certificate2 constructors → X509CertificateLoader
• ForwardedHeadersOptions.KnownNetworks → KnownIPNetworks
• X509Certificate2.PrivateKey → GetRSAPrivateKey()

Original prompt

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This section details on the original issue you should resolve

<issue_title>Update all projects to .NET 10</issue_title>
<issue_description>All the C# projects and solutions should be updated to have .NET 10 as the TargetRuntime. All the referenced packages should be updated as well to be compatible with .NET 10.

The ASP.NET Core webapps to update are available here: https://github.com/microsoft/SPID-and-Digital-Identity-Enabler/tree/main/WebApps

Ensure breaking changes don't have impact on our projects: https://learn.microsoft.com/en-us/dotnet/core/compatibility/10.0?toc=%2Fdotnet%2Ffundamentals%2Ftoc.json&bc=%2Fdotnet%2Fbreadcrumb%2Ftoc.json

</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Update all projects to .NET 10 #87

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[Copilot]

Pull request overview

This PR migrates two ASP.NET Core web applications from .NET 8 to .NET 10 by updating the target framework and associated NuGet packages. The migration addresses both framework compatibility requirements and security vulnerabilities (CVE GHSA-m5vv-6r4h-3vj9 in Azure.Identity).

• Updated target framework from net8.0 to net10.0 in both projects
• Upgraded ASP.NET Core packages from 8.0.x to 10.0.0
• Updated Azure and Microsoft Identity packages with security fixes and compatibility improvements

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
WebApps/Proxy/Microsoft.SPID.Proxy/Microsoft.SPID.Proxy.csproj	Updated target framework to .NET 10 and upgraded 9 packages including Azure.Identity (security fix), ASP.NET Core, and System packages
WebApps/CNS.Auth.Web/CNS.Auth.Web.csproj	Updated target framework to .NET 10 and upgraded 4 packages including ASP.NET Core packages and Microsoft.IdentityModel.Tokens.Saml

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[Copilot]

The Microsoft.VisualStudio.Web.CodeGeneration.Design package is still on version 8.0.8 while the project targets .NET 10. Although this package is a development-time tool and may work across versions, consider updating to version 10.0.0 if available for consistency with other package versions and to ensure full .NET 10 compatibility.

Suggested change

	<PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="8.0.8" />
	<PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="10.0.0" />