Update NanoVectorDBStorage upsert to use hash values for IDs

[FatRicePaddyyyy]

• In the delete_entity method, a hash value is calculated when deleting an entity.
• On the other hand, in the upsert method, the index was used directly as the ID when adding an entity.
• Therefore, I modified the upsert method to also calculate a hash value.

[LarFii]

Thanks for your suggestion! But the hash value is already calculated in operate.py before calling the upsert method.

[FatRicePaddyyyy]

I see. Sorry for jumping to conclusions. I'll cancel the pull request.