handle ANY type in nested values

[jraymakers]

Fix for second part of #128.

The C API returns nullptr when attempting to create a value of a nested type with a item or entry type of ANY. Note that nullptr is distinct from a duckdb_value representing a SQL NULL value; we don't want duckdb_value to ever be nullptr. So, we need to fail gracefully in this case, by throwing an exception.

In the Node Neo API, when binding values to prepared statements, the user might leave the type unspecified in a way that we can't infer (such as by passing an empty array), or they might explicitly specify the ANY type. In either case, we can end up with an ANY type (failed inference returns ANY). Rather than let the generic low-level exception through, we detect these cases and throw an error with a more specific and hopefully helpful message.

[jraymakers]

The Windows bindings tests started to fail nondeterministically for unknown reasons. I've (hopefully temporarily) skipped this run; I plan to troubleshoot later. The API tests still run (and pass).