Starting a test instance with a core tables backup fails because version table does not exist

init_db.sql does not create the `version` table, so restoring a core tables backup on startup does not work.

If the `version` table is created by init_db.sql, it has two rows after the backup is restored if init_db.sql inserts the version number row.

Start by reading init_db.sql and tracing the startup path that restores a core tables backup. Confirm how the version table and version number row are handled; done means startup restoration succeeds and the restored database has the expected single version row.

Written by the indexing model from the issue text.