Back-out all changes to automatically use RETURNING for SqliteExtDatabase, CSqliteExtDatabase and APSWDatabase. The issue I found is that when a RETURNING cursor is not fully-consumed, any parent SAVEPOINT (and possibly transaction) would not be able to be released. Since this is a backwards-incompatible change, I am going to back it out for now.
Returning clause can still be specified for Sqlite, however it just needs to be done so manually rather than having it applied automatically.