- Split transaction logger (kanta.changes) and migration logger (kanta.migrations).
- Migrations.apply() now returns MigrationResult instead of logging.
- Kanta.open() emits one info summary per DB and debug transaction per migration.
- Add open(log=...) to suppress/redirect default migration logging.
- Add @kanta.logmigr callback for custom migration logging/summaries.
- Add transaction(log=...) to suppress/redirect transaction logging.
- Update tests for the new MigrationResult API and logging behaviour.