Add a duckdb export or convert base layer to duckdb

[cmungall]

Duckdb has a lot of advantages over sqlite

• speed
• extended syntax
• built in support for arrays and other datatypes

In theory there is no particular reason for a duckdb export. You can just point duckdb at any of the semsql builds and it works. But there are some oddities that occur and it would be better to have a dedicated duckdb export

This could be a simple mirror of the sqlite. However, there is the opportunity to take advantage of increased expressivity. For example, we could have tables like

CREATE TABLE term_info (
   id VARCHAR,
   label VARCHAR,
   aliases VARCHAR[],
   ....
)