Metadata signing process

@sevanspowell hi, we soon have the feature to have the policy key on a hw-ledger. this is already working but is not released yet for the public. so we have a great security upgrade here for NFTs/NFs. the thing is, you need a signed entry for each parameter in the json file for the registry. i am not a haskell programmer, i looked at the code of the token-metadata-creator. would it be possible to get detailed information on how to sign the entries? i saw that is is based on a combinations of the black2b_256 hashes of the subject, the entry name, the value and the sequence number somehow?

i wanna collect some information so we can pass it on to vacuumlabs to discuss a maybe implementation into the cardano-app for ledger/trezor hw-wallets. because it would be bummer to have policy keys securely on a hw-wallet, but not being able to register the tokens with that policyid in the registry.