[Question] How to decode Array(Tuple()) column

Hi, I have the following column in my schema

```sql
map_arr Map(Int32, Array(Tuple(String, Array(Int32))))
```

But I couldn't find a way to create a `ColArr` of type `ColTuple`. I am new to go-lang, so it might very well be my ignorance.

I am not using the connection/query, but rather using the proto.* with `DecodeRawBlock` as described in native dump reading section to build an executable UDF.

Also, the `Dump` section in main `README.md` do not pass `version` for `DecodeRawBlock` and `EncodeRawBlock` as the current latest version requires, and it wasn't obvious which version to use.