Support Kitty graphics protocol

[EpicDima]

It seems that displaying images in the terminal is not the most necessary thing, but it would be cool to have support for this.

https://sw.kovidgoyal.net/kitty/graphics-protocol/

[JakeWharton]

Yes, this is planned. I also confirmed with Colin before Coil 3 went stable that will be able to use its core for image loading.

[JakeWharton]

There's a lot of "draw the rest of the owl" here, but we'll get there!

[JakeWharton]

One problem is that there's no way to query for support of this protocol. So we have to resort to opt-in flags and/or terminal detection. This just came up today elsewhere for someone wanting to query for support (in an unrelated context).

[kovidgoyal]

Yes, you can query support for it https://sw.kovidgoyal.net/kitty/graphics-protocol/#querying-support-and-available-transmission-mediums

[JakeWharton]

Thanks! I hadn't actually looked myself, and was going off that Ghostty issue (that you also replied to). Glad to see it's the same basic mechanism as keyboard.

[JakeWharton]

Marking as blocked. While probably not strictly true (I'm not actually sure what we can do here with Mordant), we really want #579 first where this should become trivial.