Provide an endpoint to encrypt_file / decrypt_file separately similar to encrypt_keychain / decrypt_keychain.

[HariniRajan397]

Scenario/ Problem Statement :

At BlockSurvey, we recently migrated from .org to .io domain. We wanted to check if there is any way to take a dump of files from .org Gaia and migrate it to .io Gaia.

I understand the files are encrypted with the app-key based on the combination of Blockstack id and app origin. So it is not a straight forward move. I have taken the file dump from .org domain using the below command.
$blockstack-cli gaia_dump_bucket xxx.id.blockstack https://blocksurvey.org https://hub.blockstack.org “$BACKUP_PHRASE” ./backups

But few files are encrypted with the .org domain-specific app keys. So we couldn't port the files easily.

Request for endpoint:
In this scenario, it will be very helpful if we have an endpoint to separately encrypt_file/decrypt_file. Those endpoints will enable us to decrypt the downloaded dump file and upload it to Gaia using the putFile() command. Thanks.

**Adding the forum discussion related to the same. Thanks .**https://forum.blockstack.org/t/help-needed-porting-gaia-files-from-one-domain-to-another/10789/3