[NIP93] Curatable Profile Gallery

[believethehype]

This is a small NIP to define Kind 1163 events: Profile gallery entries.

I had withdrawn my earlier pull request #1340 which would have been an addition to NIP51 to add a List for a profile gallery.
After consulting with several people, this new version uses Kind 1163 Events (Gallery entries) instead of a "replaceable list with gallery entries". The reasoning is that lists might have size limits on relays and might easily be wiped by clients and clients can filter for these events instead.

Feedback is welcome.

[pablof7z]

I'd remove the mention to kind:1; just say that, if there's another event this event is coming from, to tag it, could be a kind:1 or something else.

Also, relay hints and pubkey hints apply, worth being explicit about them if you're going to include an e tag example.

I would mention that an accompanying text could be added on the content for display alongside the image (like a caption)

[believethehype]

Updated with relay hint, optional caption in content and removed reference to Kind 1

[flox1an]

• Is the e tag required or optional? Can there be 1163 with just an url without an event reference?
• I don't know if anyone uses them but maybe the blurhash from 1063 may be useful for a quick preview? Also it might be helpful to have width and height (or dim) for rendering the gallery.
• Should we add an optional x tag for the content sha256 content hash to make it blossom compatible?

[believethehype]

An e tag is mandatory, as it references to a note (and the social aspects like comments, reactions, zaps around it).

I think other (potentially optional) parameters from NIP94 (kind 1063) could be added if that helps clients rendering. I think for example from Amethyst it's not a problem to add x, dim, mimeType and blurhash.

I added that NIP94 File Metadata can optionally be used in kind 1163 events.