Fix collection embedding names

[sebnapi]

The original problem was that

f"{prefix}_embedding_hf_{start_date}".replace("-", "_")

was not following the convention that two underscores seperate the start_date.

This can be easily refactored into the parent class and made more robust by utilizing the model_name, so that we never compare vectors between different embedding models and never find ourselves creating a oversight bug like this again.

[sebnapi]

These changes fixed the code for me.

[finaldie]

Thank you so much @sebnapi for consolidating all these and unified the logic (also make the HuggingFace part working).

I'll merge it and create a new tag soon 👍