Bundled database drivers for narwhal.
Each engine (postgres, mysql, sqlite, duckdb, clickhouse,
mssql) lives behind a cargo feature of the same name. Enabling the
all-drivers umbrella turns them all on; the narwhaldb binary
relies on this. Library consumers pick what they need:
= { = "1", = false, = ["postgres", "sqlite"] }
The crate also re-exports [registry::DriverRegistry] as
[DriverRegistry], which replaces the v1.x narwhal-driver-registry
crate.