Repair Count logic

https://github.com/linksplatform/Data.Doublets/blob/86197375ad05039154d0c706d070b5e2a2cfed5a/csharp/Platform.Data.Doublets/Memory/Split/Generic/SplitMemoryLinksBase.cs#L491-L503

```cs
if (AreEqual(source, any))
{
if (AreEqual(storedLinkValue.Target, target))
{
return GetOne();
}
}
if (AreEqual(target, any))
{
if (AreEqual(storedLinkValue.Source, source))
{
return GetOne();
}
}
return GetZero();
```

Note that this should also affect C++ code base. As @uselessgoddess told me, it is already fixed in Rust code base.

Start with csharp/Platform.Data.Doublets/Memory/Split/Generic/SplitMemoryLinksBase.cs at lines 491-503, then locate the corresponding C++ implementation. Compare both with the already-fixed Rust code to determine the intended Count behavior; done means the C# and C++ logic is consistent with Rust.

Written by the indexing model from the issue text.