Upsert logic needs to be redesigned

[mpgreg]

Describe the bug
Current code is not atomic and is not batch safe. Also no roll-back.

If a documents chunks span a batch the upsert will remove docs and reinsert in one batch and then redo it in the next batch. Documents inserted in the first batch will be deleted and no inserted.

Version

To Reproduce
Steps to reproduce the behavior:

Expected behavior
Upsert should be atomic, batch-safe and allow roll-back if any of the batches fail.

Screenshots

Additional context

[mpgreg]

This is really a bug for the pre-release weaviate provider but documenting here since it impacts ask astro.