Db
lib/driver/db.march Abstract database connection — driver seam between the wire layer and all higher-level depot modules.
This module does NOT import Sqlite. SQLite dispatch is provided as a concrete SqliteOps record in SqliteConn, so the Ffi capability stays contained in lib/driver/sqlite.march. Callers that only import Db do not inherit Ffi requirements.
Adding a new backend:
- Add a constructor to DbConn.
- Provide an open_* function in the backend module (see Sqlite.open_conn).
- Add dispatch arms to exec/query/dialect/close/conn_key below.