Querying with a nullable struct param always returns null

When querying for a nullable struct type, it's always returning null, even if the query returns results.

In the below example, they have the identical query - the first one is populated correctly, and the second one is null. This holds true for the other Query methods like Query, QueryFirst, etc.

There was a similar issue for tuples: #1399 - but that was resolved in 2020 so I'm guessing this is something different.

Foo f1 = conn.QueryFirstOrDefault<Foo>("SELECT 1 AS [ID], 'Something' AS [Name];");
Console.WriteLine(JsonSerializer.Serialize(f1));
Foo? f2 = conn.QueryFirstOrDefault<Foo?>("SELECT 1 AS [ID], 'Something' AS [Name];");
Console.WriteLine(JsonSerializer.Serialize(f2));

public struct Foo
{
    public int ID { get; set; }
    public string Name { get; set; }
}

Start by reproducing the issue with the provided C# Foo struct and SELECT query, then trace the QueryFirstOrDefault path used for nullable structs and compare it with the non-nullable case. Done means Foo? is populated from the returned row for QueryFirstOrDefault and related Query methods, with a regression test covering the behavior.