feat(csharp): Initial changes for ADBC 1.1 in C# implementation

[CurtHagenlocher]

This adds all the basic elements defined since the initial ADBC 1.0 specification. There's still a bunch of cleanup likely to be required, including support for exporting an ADBC 1.1 driver. There's also no test coverage (boo! hiss!) as the DuckDB driver does not yet implement any 1.1 features and some ci infrastructure work is probably needed to support other drivers.

Closes #1215

[CurtHagenlocher]

@davidhcoe I'd appreciate your opinion on this change; at your leisure, of course.

[davidhcoe]

Overall, this is a good step toward a 1.1 implementation. I am not sure how we got the BulkIngest method in AdbcConnection, since the spec doesn't define that, but Java has it too, so we will need to clean that up at some point.

The other part I don't know about is whether having SetOption(string, object) is sufficient to having the SetOptionByte, SetOptionInt, etc., methods that are defined in the spec. I see they are defined in the C importer/exporter, though, just not in the core C# definitions. I think this is largely because having different methods means having different dictionaries as well, which would seem strange to have to go look through different dictionaries to find where a value is.

[CurtHagenlocher]

If we want to pass all the initial options in at once when we construct something, then they kind of have to be represented as "object". Post construction, it might be justified to have separate overloads for setting different types but I also feel like this is an area where it's reasonable to want to support both e.g. SetOption("adbc.x", "true") and SetOption("adbc.x", true) for a bool-valued option that's officially represented as a string. And if we're going to convert anyway... .