main
black: Reformat with Black 23.
migrations: Squash most confirmation migrations.
migrations: Tweak realm foreign key dependency.
migrations: Import BaseDatabaseSchemaEditor from its canonical module.
confirmation: Migrate Confirmation to bigint.
models: Migrate ids of all non-Message-related tables to bigint.
confirmation: Move zerver dependency to correct migration.
ruff: Fix RUF059 Unpacked variable is never used.
confirmation: Replace RealmCreationKey - use Confirmation instead.
Include autogenerated initial migrations for South.