Replies a post's author approves (FEP-5624), checked live with PeerTube

PeerTube puts canReply on a video whose comments wait for approval, and answers each comment with ApproveReply. A
persona's reply to such a post now waits (privapub.approval: pending), its Create going to the author alone; the
author's ApproveReply, signed by the author and naming the post answered, lets it out to its audience with
replyApproval, and RejectReply leaves it ours. A null canReply (PeerTube's open comments) says nothing; an empty one
refuses. The PeerTube scenario holds a comment for review and approves it through PeerTube's API (28 checks).

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

PrivaPub/Federation/Rendering/ActivityPubRenderer.cs

@@ -63,6 +63,7 @@ namespace PrivaPub.Federation.Rendering
 				["AnnounceAuthorization"] = "gts:AnnounceAuthorization",
 				["likeAuthorization"] = new JsonObject { ["@id"] = "gts:likeAuthorization", ["@type"] = "@id" },
 				["replyAuthorization"] = new JsonObject { ["@id"] = "gts:replyAuthorization", ["@type"] = "@id" },
+				["replyApproval"] = new JsonObject { ["@id"] = "toot:replyApproval", ["@type"] = "@id" },
 				["announceAuthorization"] = new JsonObject { ["@id"] = "gts:announceAuthorization", ["@type"] = "@id" },
 				["litepub"] = "http://litepub.social/ns#",
 				["EmojiReact"] = "litepub:EmojiReact",
@@ -408,6 +409,8 @@ namespace PrivaPub.Federation.Rendering
 			// the parent's author let this reply in (GoToSocial's interaction policies)
 			if (!string.IsNullOrEmpty(inReplyTo) && !string.IsNullOrEmpty(post.ApprovalURI))
 				note["replyAuthorization"] = post.ApprovalURI;
+			if (!string.IsNullOrEmpty(inReplyTo) && !string.IsNullOrEmpty(post.ReplyApprovalURI))
+				note["replyApproval"] = post.ReplyApprovalURI;
 			if (post.EditedAt.HasValue)
 				note["updated"] = Timestamp(post.EditedAt.Value);
 			return note;