Preserve invalid friend assembly diagnostics by removing lossy HRESULT roundtrip

[Copilot]

This addresses a misleading FileLoadException path triggered by invalid InternalsVisibleTo metadata (e.g., specifying both PublicKey and PublicKeyToken). Instead of surfacing a generic load failure, the runtime now preserves the underlying assembly-name parse failure details.

• ## Description
  • CoreCLR error-path change
    • In FriendAssemblyDescriptor::CreateFriendAssemblyDescriptor (src/coreclr/vm/assembly.cpp), switched from InitNoThrow + THROW_HR_ERROR_WITH_INFO(...) to throwing Init(...) directly.
    • This avoids the HRESULT-based rethrow that dropped the original diagnostic context and produced a confusing file-load error.
  • Regression coverage
    • Added Loader/classloader/regressions/InvalidFriendAssemblyName test project.
    • New test uses an intentionally invalid InternalsVisibleTo string and asserts the thrown FileLoadException carries the invalid assembly identity and a message indicating invalid assembly name.

// Before
hr = pFriendAssemblyName->InitNoThrow(displayName);
if (SUCCEEDED(hr))
{
    hr = pFriendAssemblyName->CheckFriendAssemblyName();
}
if (FAILED(hr))
{
    THROW_HR_ERROR_WITH_INFO(hr, pAssembly);
}

// After
pFriendAssemblyName->Init(displayName);
hr = pFriendAssemblyName->CheckFriendAssemblyName();

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