sqlite-utils 4.0, now with database schema migrations

This article announces the release of sqlite-utils 4.0, a major update to the Python utility for SQLite databases. It introduces three key features: database schema migrations using Python files, nested transactions via a new db.atomic() method, and support for compound foreign keys. The migration system allows defining sequences of schema changes, tracking applied migrations, and using table.transform() for advanced alter table operations. The article includes examples of creating migration files, running them with the command-line tool, and viewing migration status. This is a technical update relevant to developers working with SQLite databases.