Guid on how to use Postgres (or any other) extension with ADBC

There is an issue similar to this https://github.com/apache/arrow-adbc/issues/546 that talks about geo extension and how one can use it with ADBC.
My general question is around the guides for using Postgres Extensions? How one should enable them and is there any easy way to work with them from the client? I use Scala.
In particular, I was wondering what are the steps to work with [pgvector](https://github.com/pgvector/pgvector). It introduces `vector` data type and also new expressions (functions, aggregators, etc.)