.dump doesn't use a transaction (sqlite3 does)

Output of an empty database using sqlite3 dump. Note the transaction that's always present:

```
PRAGMA foreign_keys=OFF;
BEGIN TRANSACTION;
COMMIT;
```

What the libsql shell outputs:

```
PRAGMA foreign_keys=OFF;
```

libsql should also wrap all of the sqlite commands in a transaction in the same way that sqlite3 does.