[Feature request] Adding SHA256

[TaxMachine]

it would be great to have in the json the sha256/512 to check the images integrity

[galpt]

it would be great to have in the json the sha256/512 to check the images integrity

I'd say implementing a hash system is possible with Go since I've done this with hashing zip files, which technically gives more burden to the server compared to hashing images.

So it needs to hash an image once and save the hash somewhere, and give it as a json response for future requests,
or the server could just hash the image everytime it receives a request, no need to save the hashes at all in this case.

Let's wait for another opinion from the repo maintainer(s).