nixpkgs dbt has no Databricks adapter; use uv per project

nixpkgs (late 2026) ships dbt 1.11.2 with a dbt.withAdapters passthru, but only dbt-postgres, dbt-bigquery, dbt-redshift and dbt-snowflake are packaged as adapters; dbt-databricks is missing. Bare dbt with no adapter cannot connect anywhere. For Databricks, skip Nix and use uv add dbt-databricks per project (uv run dbt ...); more adapters like dbt-postgres can be added to the same project. apache-airflow 3.3.2 is in nixpkgs as a top-level package (not under python3Packages), but per-project uv with airflow standalone is easier because the provider packages vary by project.