libpg-query-node already supports AST types via `@pgsql/types` which is generated by `pg-proto-parser` (using the protobuf file in libpg_query): https://github.com/launchql/pg-proto-parser

(v15 exports these, I think they still need to be added to v16).

I've worked with the maintainers of libpg-query-node and they are very friendly and open to improvements. My suggestion would be to work with them to upstream useful changes vs. forking.