[Enhancement]: Migrate to BOSS gRPC service

[jonbarrow]

Checked Existing

• I have checked the repository for duplicate issues.

What enhancement would you like to see?

Right now the site relies on downloading data from the BOSS server. Instead, we should consider moving to gRPC for this as https://github.com/PretendoNetwork/grpc/tree/master/protobufs/boss/v2 already exists

Any other details to share? (OPTIONAL)

This feature cannot be implemented at the moment, as the BOSS gRPC protobufs lack a way to request file contents. An API for this should be discussed first before jumping into it, @DaniElectra thoughts? If we allow the data to be decrypted as well when requested, then we can remove the need for storing the BOSS keys here as well

[DaniElectra]

I agree with adding a way to get the file contents over gRPC. We can probably make the API so that we give the data_id and it returns all of the files payload data (PayloadContentCTR on 3DS or just the raw data on Wii U). The rest of metadata can be obtained with ListFilesX beforehand