Upgrade CloudStorage package + pipelines to .NET 10

[Copilot]

This PR moves the package and build/release process to .NET 10 and aligns framework-bound dependencies/documentation accordingly. Scope is limited to target framework, SDK workflow setup, and minimal dependency/version updates needed for a clean .NET 10 restore.

• Framework targeting

  • Updated library and test projects from net9.0 to net10.0.

• Dependency alignment

  • Updated Microsoft.Extensions.DependencyInjection to 10.0.0.
  • Updated ICG.NetCore.Utilities to 9.0.1 (latest available compatible release).

• Build/release process

  • Updated GitHub Actions workflow SDK setup from 9.0.x to 10.0.x in CI and release workflows.

• README

  • Added a concise framework support note indicating current .NET 10 target.

<!-- AspNetCore.Utilities.CloudStorage.csproj -->
<PropertyGroup>
  <TargetFramework>net10.0</TargetFramework>
</PropertyGroup>

<ItemGroup>
  <PackageReference Include="ICG.NetCore.Utilities" Version="9.0.1" />
  <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="10.0.0" />
</ItemGroup>

• Fixes Update Package to .NET 10 #104