Scheduled posts: written now, published at their time

POST /api/v1/statuses with scheduled_at no longer posts at once: the post is
kept as asked (at least five minutes ahead; 300 waiting, 25 a day, as
Mastodon allows), its media kept from the janitor, and a PublishScheduled job
publishes it at its time as the persona. scheduled_statuses lists, moves and
drops them; a moved post's old job finds it not due. Idempotency-Key holds
for scheduling too.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw

PrivaPub/Api/Mastodon/Controllers/MediaController.cs

@@ -101,12 +101,14 @@ namespace PrivaPub.Api.Mastodon.Controllers
 			return new EmptyResult();
 		}
 
-		object View(MediaAttachment attachment) => new
+		object View(MediaAttachment attachment) => View(_media, attachment);
+
+		internal static object View(IMediaService media, MediaAttachment attachment) => new
 		{
 			id = attachment.ID,
 			type = attachment.Kind,
-			url = _media.Url(attachment.FilePath),
-			preview_url = _media.Url(attachment.PreviewPath ?? attachment.FilePath),
+			url = media.Url(attachment.FilePath),
+			preview_url = media.Url(attachment.PreviewPath ?? attachment.FilePath),
 			remote_url = default(string),
 			text_url = default(string),
 			meta = new