VACUUM INTO fails to save in-memory SQLite databases to disk

Saving an in-memory SQLite database to disk with ExecuteSQL("VACUUM main INTO 'path';") can return successfully without creating the destination file. The same operation succeeds when the source database is file-based.

The command should create a persistent SQLite database containing the source schema and data, or raise a database error if the destination cannot be written. Applications currently receive no indication that their backup was not saved.