[Feature] Does FerretDB work for this project in place of MongoDB?

## About

MongoDB changed to a non-free license SSPL. FerretDB aims to be a drop-in replacement for MongoDB, but the project is still in development. Do you know if FerretDB's available features would work for Kaetram-Open?

### Possible implementation

Instead of MongoDB, FerretDB might work.

### Alternative implementation


### Additional context

