Everything on, phase 4a: one answer everywhere for counts, search, collections and the instance API

Owner decision 2026-10-04: fix the mismatches and every other mismatch of the same kind.

- One counting rule (Domain/Privacy/Counted), Mastodon's. It is used for a persona's statuses_count, its outbox
  totalItems, NodeInfo localPosts and the instance status_count, which used to count four different things. It
  counts every post that is neither deleted nor a DM, boosts included, and circle and located posts too (owner
  decision). A group's count includes its remote members' posts.
- Users. Personas of banned or deleted roots no longer count, and are not found in search. NodeInfo now gives
  activeMonth and activeHalfyear, and the v2 instance gives active_month instead of a constant 0.
- replies_count counts only public and unlisted replies, so it no longer tells anyone that a private reply exists.
  Migration _012 recounts it.
- A remote account that deletes itself takes everything out of every count (GoneActors): its likes, downvotes,
  reactions and poll votes go and their counters come back, as do its boosts', replies' and quotes' counts, and its
  notifications. Lookups, account lists, search and favourited_by no longer show it. Migration _012 applies this to
  accounts already gone.
- Deleting a post also deletes its pins and the local boosts of it.
- /stalking gives the same total as following_count. Members are still never listed, and hide_collections is now
  always true, since the setting never did anything.
- Joining a community by invitation is following it, so /flock and /groupies agree; leaving unfollows.
- Search. Anyone may search, as on Mastodon; resolve and offset need a sign-in, offset pages, and deleted accounts
  are never found.
- notifications/unread_count counts what the list shows, and the owner's follower and following lists page with
  Link.
- The instance API advertises what is enforced:
  - max_characters, now enforced with a 422;
  - max_pinned_statuses = MaxPins;
  - the media types and limits MediaService and MediaOptions accept;
  - PollService's limits;
  - the configured languages;
  - no streaming URL until streaming exists.

  domain_count counts the servers we have exchanged with; which ones stays unpublished (peers is empty).
- Routes Mastodon answers now answer instead of 404:
  - directory, tags/{name}, timelines/link and identity_proofs;
  - instance/languages, translation_languages, domain_blocks and privacy_policy;
  - the v1 and v2 notification policy, and notification requests.

Also, from phase 3: a recovered password ends /clientapi sessions through a per-root SessionStamp claim instead of
comparing the JWT's whole-second nbf with the change time. That comparison let a token issued in the same second
survive, which made a test flaky.

671 tests pass.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ELjqpznMFMNrJoJUj6K5p2

PrivaPub/Api/Mastodon/Controllers/AccountsController.cs

@@ -71,8 +71,7 @@ namespace PrivaPub.Api.Mastodon.Controllers
 				avatar.Settings.IsDiscoverable = discoverable;
 			if (Params.Bool("indexable") is { } indexable)
 				avatar.Settings.IsIndexable = indexable;
-			if (Params.Bool("hide_collections") is { } hide)
-				avatar.Settings.HideCollections = hide;
+			// hide_collections stays true: who follows whom is never listed here, only counted (FEDERATION.md)
 			if (Params.Get("source[privacy]") is { } privacy && privacy is "public" or "unlisted" or "private")
 				avatar.Settings.DefaultVisibility = privacy;
 			if (Params.Bool("source[sensitive]") is { } sensitive)
@@ -120,7 +119,7 @@ namespace PrivaPub.Api.Mastodon.Controllers
 			}
 			var userName = parts[0];
 			var domain = parts[1].ToLowerInvariant();
-			var foreign = await _dbEntities.ForeignAvatars.Match(f => f.UserName == userName && f.Domain == domain).ExecuteFirstAsync(token);
+			var foreign = await _dbEntities.ForeignAvatars.Match(f => f.UserName == userName && f.Domain == domain && !f.DeletionAt.HasValue).ExecuteFirstAsync(token);
 			return foreign == default ? NotFoundError() : Json(_mapper.Foreign(foreign));
 		}
 
@@ -197,8 +196,9 @@ namespace PrivaPub.Api.Mastodon.Controllers
 			var (local, _) = await Find(id, token);
 			if (local == default || local.Id != MyId)
 				return Json(Array.Empty<Account>());
-			var followers = await _dbEntities.Followers.Match(f => f.LocalActorId == local.Id && f.LocalActorKind == local.Kind && f.IsAccepted)
-				.Sort(f => f.ID, Order.Descending).Limit(Limit(40, 80)).ExecuteAsync(token);
+			var followers = await Page.From(Params, Limit(40, 80))
+				.Fetch(_dbEntities.Followers.Match(f => f.LocalActorId == local.Id && f.LocalActorKind == local.Kind && f.IsAccepted), f => f.ID, token);
+			Link($"/api/v1/accounts/{id}/followers", followers.LastOrDefault()?.ID, followers.FirstOrDefault()?.ID);
 			return Json(await AccountsFor(followers.Select(f => f.ActorURI), token));
 		}
 
@@ -208,8 +208,9 @@ namespace PrivaPub.Api.Mastodon.Controllers
 			var (local, _) = await Find(id, token);
 			if (local == default || local.Id != MyId)
 				return Json(Array.Empty<Account>());
-			var following = await _dbEntities.Followings.Match(f => f.AvatarId == local.Id && f.State == FollowState.Accepted)
-				.Sort(f => f.ID, Order.Descending).Limit(Limit(40, 80)).ExecuteAsync(token);
+			var following = await Page.From(Params, Limit(40, 80))
+				.Fetch(_dbEntities.Followings.Match(f => f.AvatarId == local.Id && f.State == FollowState.Accepted), f => f.ID, token);
+			Link($"/api/v1/accounts/{id}/following", following.LastOrDefault()?.ID, following.FirstOrDefault()?.ID);
 			var accounts = await _mapper.Accounts(following.Select(f => f.TargetAccountId), token);
 			return Json(following.Select(f => accounts.GetValueOrDefault(f.TargetAccountId)).Where(a => a != default).ToList());
 		}