Serialization issues - Orleans 8.0.0

[claylaut]

We're migrating from Orleans 3.7.1 to Orleans 8.0.0.

Currently, we have these two issues:

Issue 1
When a class inherits from a generic list. Currently, the codegen is skipping this and on runtime, it's throwing an error: Could not find a base type serializer.

I've added a simple failing unit test (currently skipped) so you have an easy repro of this issue. #8858

Issue 2
As per doc https://learn.microsoft.com/en-us/dotnet/orleans/host/configuration-guide/serialization?pivots=orleans-7-0#serializing-record-types

When using GenerateCodeForDeclaringAssembly for an external lib and Sdk is not added to the library
Just added a failing test (which is skipped) with a repro #8860

[stephenlautier]

We also have another issue which is harder to reproduce in tests

namespace Odin.Mimir.Shared.Universe;

[Immutable]
[GenerateSerializer]
public sealed class UniverseIndexQuery : MimirOrleansComplexQuery<UniverseIndexQuery, IUniverseIndices>
{
}

The problem is IUniverseIndices. When its sourcegened the namespace is not resolved, and instead its simply emitted as IUniverseIndices;
IUniverseIndices itself is generated through our sourcegen (custom), so most probably thats why its namespace is not resolved.

SourceGen	Error

This is the source of our generated IUniverseIndices

[ReubenBond]

Please open a separate issue for "Issue 2" and the IUniverseIndices issue so we can track a fix. They might be caused by the same issue.

[claylaut]

@ReubenBond I've just created a new issue for issue 2.
#9006

[claylaut]

@ReubenBond I've just created a new issue for issue 3
#9007