fix: notification pushes now match what the 2023 client reads

Most pushes were still shaped for the 2020 watch, so the 2023 client
parsed them as empty or dropped them without any error.

- RelationshipChanged carries the relationship row, to both players, on
  friend request / accept / remove / add and on favorite / mute / ignore.
  Friend requests and accepts also land in the notifications inbox.
- ModerationKick uses the client's flat moderation block, with the
  reason in VoteKickReason (the only field the dialog shows).
- Bans, account deletion, password resets and second-session takeover
  are a Logout with a numeric reason instead of a kick to the dorm; the
  old string reason failed the client's parse.
- SubscribeToPlayers is honoured: each connection joins a presence group
  per subscribed player, and presence (only presence) reaches subscribers
  as well as friends. The hub allows 180 s of client silence, since the
  client reconnects at most 3 times per login.
- Admin broadcast sends its text as a coach message and can start the
  client's own maintenance countdown; ServerMaintenance only reads
  StartsInMinutes.
- ConsumableMapping, StorefrontBalance, gift, player event, level-up,
  RoomUpdate, profile-image and PlayerLeftChat pushes carry the client's
  DTOs. "Join rejected" is the client's RequestGameInvite message.

Contract in docs/recroom-2023-notifications.md; push frames are checked
by NotificationContractTests through a capturing hub context.

DorkNet.Server/Services/PresenceBroadcastService.cs

@@ -36,7 +36,10 @@ public static class PresenceVisibility
 /// RecNet.Runtime/RecNet/Matchmaking.txt:1436) feeds the payload straight into
 /// FLAOOBNJAAD (:6917), the same routine the heartbeat uses to apply an out-of-sync
 /// correction (:18467). A frame about the LOCAL player therefore moves that player, so
-/// these frames go to friends only, never to the subject.
+/// these frames never go to the subject. They go to the subject's friends and to every
+/// other connection that subscribed to the subject with SubscribeToPlayers (see
+/// NotifyHub.SubscribeToPlayers); non-friends only see the real presence when it is
+/// Public.
 /// </summary>
 public sealed class PresenceBroadcastService(
     IServiceScopeFactory scopes,
@@ -58,7 +61,7 @@ public sealed class PresenceBroadcastService(
         presence.IsRecentlyActive(playerId) || connections.GetConnections(playerId).Count > 0;
 
     /// <summary>Push the player's current presence (online state + committed
-    /// room) to every friend.</summary>
+    /// room) to every friend and subscriber.</summary>
     public Task PublishCurrentAsync(long playerId) => PublishAsync(playerId, forceOffline: false);
 
     /// <summary>Push an offline frame regardless of any lingering markers —
@@ -105,7 +108,6 @@ public sealed class PresenceBroadcastService(
                 .Where(id => id != playerId)
                 .Distinct()
                 .ToList();
-            if (friendIds.Count == 0) return;
 
             var online = !forceOffline && IsOnline(playerId);
             var room = online ? presence.GetRoom(playerId) : null;
@@ -134,6 +136,20 @@ public sealed class PresenceBroadcastService(
                 await notifications.PlayerPresenceChanged(visibleTo, playerId, room, online, visibility);
             if (hiddenFrom.Count > 0)
                 await notifications.PlayerPresenceChanged(hiddenFrom, playerId, null, false, visibility);
+
+            // Everyone else who subscribed to this player (SubscribeToPlayers:
+            // people in the same room, an open profile). They are not friends,
+            // so they see the real presence only when it is Public, and the
+            // offline frame otherwise. Friends were served above and the
+            // subject must never get a frame about themselves, so their
+            // connections are excluded.
+            var exclude = connections.GetConnections(playerId)
+                .Concat(friendIds.SelectMany(connections.GetConnections))
+                .Distinct()
+                .ToList();
+            var publicToAll = visibility == PresenceVisibility.Public && online;
+            await notifications.PresenceToSubscribersAsync(
+                playerId, publicToAll ? room : null, publicToAll, visibility, exclude);
         }
         catch (Exception ex)
         {