[release/10.0.1xx] update to 10.0.4 runtime workloads

[jonathanpeppers]

The Mono/Emscripten workloads look like they are only updated via the .NET 10.0.1xx SDK channel, manually updating for now:

> darc update-dependencies --name Microsoft.NET.Workload.Mono.ToolChain.Current.Manifest-10.0.100 --id 302542
Updating 'Microsoft.NET.Workload.Mono.Toolchain.Current.Manifest-10.0.100': '10.0.103' => '10.0.104' (from build '20260219.1' of 'https://github.com/dotnet/dotnet')
Checking for coherency updates...done.
Applying updates...    done.

> darc update-dependencies --name Microsoft.NET.Workload.Emscripten.Current.Manifest-10.0.100 --id 302542
Updating 'Microsoft.NET.Workload.Emscripten.Current.Manifest-10.0.100': '10.0.103' => '10.0.104' (from build '20260219.1' of 'https://github.com/dotnet/dotnet')
Checking for coherency updates...done.
Applying updates...    done.

Will review how we can automate this for future updates.

[Copilot]

Pull request overview

This PR updates the Mono and Emscripten workload manifests from version 10.0.103 to 10.0.104 for the .NET 10.0.1xx SDK. The update was performed manually using the darc update-dependencies command, as these workloads are currently only updated via the .NET 10.0.1xx SDK channel. The changes track build 20260219.1 from the dotnet/dotnet repository.

Changes:

• Updated Mono and Emscripten workload manifest versions from 10.0.103 to 10.0.104
• Updated dependency SHA references to match the new build (69600372e5b6e4a27587423ec6997a46079ea3fc)
• Added corresponding NuGet package source for the new build

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
eng/Versions.props	Bumped MicrosoftNETWorkloadMonoToolchainCurrentManifest100100PackageVersion and MicrosoftNETWorkloadEmscriptenCurrentManifest100100PackageVersion from 10.0.103 to 10.0.104
eng/Version.Details.xml	Updated version numbers and SHA references for both Mono and Emscripten workload manifests to track the new build
NuGet.config	Added new darc package source for the updated build, following the established naming convention (7-char SHA in key, 8-char in URL)

[rolfbjarne]

@jonathanpeppers we don't have these dependencies; maybe you don't need it in the first place (or maybe we need them too...)?

[jonathanpeppers]

@rolfbjarne I'll find out what we should do here in a meeting on Monday -- with .NET SDK team.

There is a regression in Android NativeAOT (which is OK, it's extremely experimental) -- and we definitely weren't getting codeflow from runtime to see it.