Add ability to specify ducklake options to ducklake config

[seandavi]

Apologies if I missed it in the docs. But there are a few ducklake-specific configuration options that would be nice to add to the sqlmesh ducklake config. An alternative is to document how to run a duckdb SQL script in the duckdb instance that is attaching the ducklake (after ducklake is installed and attached).

[ckarnes]

It would be great if some of the other ducklake-specific connectivity parameters could be specified as well, such as METADATA_SCHEMA.

One thing that sqlmesh appears to do when it tries to connect to a new ducklake in postgres for instance is that it silently defaults to a schema of public, when the ducklake extension defaults to a schema of main, and there are several howto's floating about that define a schema of ducklake. It might reduce confusion for new users who query the schema that they used to create their ducklake instance, but do not see what they expect.

[justbry]

Please review and accept this PR to add support for METADATA_SCHEMA:
#5456