Signify / Minisign Support?

I recently came across [Minisign](https://jedisct1.github.io/minisign/) as an alternative way to generate a pub/private keyset, and was wondering if there would be a chance that we could see support so we could add this type of public key to our profiles. I've had a look at the homepage for [Minisign](https://jedisct1.github.io/minisign/), and it is using the [Ed25519 public-key signature system](https://ed25519.cr.yp.to/).

Start by reviewing the linked Minisign homepage and the Ed25519 public-key signature-system reference to understand the requested key format. Determine what support for adding a Minisign public key to profiles would need to cover; the issue provides no files or tests, so completion criteria require clarification.

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