A follow of a persona's profile page; an Update under its Create's id

Forte follows a persona by its profile page (/@name, WebFinger's alias) rather than its actor's id: Follow and
Undo{Follow} now find the persona by either (it was a 404). Forte also sends an edit only added to the thread's context
(FEP-171b), under the same activity id as the post's Create: the unwrapping now tells two activities that share an id
apart by what they carry, as the inbox does, so the Update is not taken for a copy.

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

PrivaPub/Federation/Inbox/ConversationContainers.cs

@@ -32,9 +32,13 @@ namespace PrivaPub.Federation.Inbox
 				Arrival.Drop("container-unusable");
 				return true;
 			}
-			var payload = new InboxPayload(actorUri, inner.ToJsonString(), "shared", ReceivedAt: DateTime.UtcNow, ForwardedBy: owner.ActorURI);
-			var queued = await queue.Enqueue(JobKind.ProcessInbox, JsonSerializer.Serialize(payload), new Uri(actorUri).Host.ToLowerInvariant(),
-				"inbox|forwarded|" + innerId, token);
+			var payload = JsonSerializer.Serialize(new InboxPayload(actorUri, inner.ToJsonString(), "shared", ReceivedAt: DateTime.UtcNow, ForwardedBy: owner.ActorURI));
+			var host = new Uri(actorUri).Host.ToLowerInvariant();
+			var dedupe = "inbox|forwarded|" + innerId;
+			var queued = await queue.Enqueue(JobKind.ProcessInbox, payload, host, dedupe, token);
+			// one id for two activities (Forte's Update of a post has its Create's id): what each carries tells them apart
+			if (!queued && InboxReceiver.CarriesOther(await queue.Payload(dedupe, token), inner))
+				queued = await queue.Enqueue(JobKind.ProcessInbox, payload, host, $"{dedupe}|{InboxReceiver.Digest(inner)}", token);
 			if (queued)
 				Arrival.Accept("unwrapped");
 			else

PrivaPub/Federation/Inbox/Handlers/FollowHandler.cs

@@ -43,7 +43,7 @@ namespace PrivaPub.Federation.Inbox.Handlers
 			var follow = activity;
 			var follower = actor;
 
-			var target = await _localActors.FindByUri(Id(follow["object"]), token);
+			var target = await _localActors.FindByAddress(Id(follow["object"]), token);
 			if (target is not { IsFederated: true } || target.Kind == LocalActorKind.Application)
 			{
 				Arrival.Drop("unknown-recipient");

PrivaPub/Federation/Inbox/Handlers/UndoHandler.cs

@@ -83,7 +83,7 @@ namespace PrivaPub.Federation.Inbox.Handlers
 		{
 			var followers = await _dbEntities.Followers.Match(f => f.ActorURI == actor.ActorURI).ExecuteAsync(token);
 			var targetUri = inner is JsonObject ? Id(inner["object"]) : default;
-			var target = targetUri == default ? default : await _localActors.FindByUri(targetUri, token);
+			var target = targetUri == default ? default : await _localActors.FindByAddress(targetUri, token);
 			var undone = false;
 			foreach (var follower in followers)
 			{

PrivaPub/Federation/Inbox/InboxReceiver.cs

@@ -225,7 +225,7 @@ namespace PrivaPub.Federation.Inbox
 
 		static string HostOf(string uri) => Uri.TryCreate(uri, UriKind.Absolute, out var parsed) ? parsed.Host.ToLowerInvariant() : default;
 
-		static bool CarriesOther(string earlierPayload, JsonNode activity)
+		public static bool CarriesOther(string earlierPayload, JsonNode activity)
 		{
 			if (earlierPayload == default)
 				return false;
@@ -235,7 +235,7 @@ namespace PrivaPub.Federation.Inbox
 		}
 
 		// what an activity carries, short: its type, actor and object
-		static string Digest(JsonNode activity) =>
+		public static string Digest(JsonNode activity) =>
 			Convert.ToHexString(System.Security.Cryptography.SHA256.HashData(System.Text.Encoding.UTF8.GetBytes(
 				$"{Value(activity, "type")}\n{Id(activity["actor"])}\n{activity["object"]?.ToJsonString()}")))[..16].ToLowerInvariant();
 
@@ -252,7 +252,8 @@ namespace PrivaPub.Federation.Inbox
 			switch (type)
 			{
 				case "Follow":
-					var target = await _localActors.FindByUri(Id(inner), token);
+					// (by its actor's id, or the profile page Forte names instead)
+					var target = await _localActors.FindByAddress(Id(inner), token);
 					if (target is not { IsFederated: true } || target.Kind == LocalActorKind.Application)
 						return new(StatusCodes.Status404NotFound, "no such local actor", Reason: "unknown-recipient");
 					break;