Hi, Moritz.
Why do you expect packages to be available via SQL coding? It's not an SQL development artifact (i.e. not just a dictionary object), but a repository object. Package concept in HANA is not the same as Oracle packages or something like that. Also it can include XS files, that have nothing for SQL.
Regarding your question: there's no any SQL statement that allows you to create packages. They are created via HANA REST APIs. And it's not related to MaxDB, because HANA is another database (and more, an application platform).
Regards,
Andrey.