Merge branch 'phase/45-presence-talk'

# Conflicts:
#	docs/phases/README.md
#	src/HSchool.Server/Api/PeopleModels.cs
#	src/HSchool.Server/Game/PersonCardReader.cs

src/HSchool.Simulation/School.cs

@@ -218,6 +218,23 @@ public sealed class School : IDisposable
 
     public IReadOnlyList<PresenceSnapshot> CapturePresence() => PresenceSystem.Capture(this);
 
+    /// <summary>
+    /// Live circle for the presence frame and the person card. Null when this person is not talking.
+    /// Member ids include self and are sorted; names stay off the wire.
+    /// </summary>
+    public TalkCirclePresence? TalkCircleOf(string personId)
+    {
+        if (!TalkCircleByPerson.TryGetValue(personId, out var circleId)
+            || !TalkCirclesById.TryGetValue(circleId, out var circle))
+        {
+            return null;
+        }
+
+        var members = circle.Members.ToArray();
+        Array.Sort(members, StringComparer.Ordinal);
+        return new TalkCirclePresence(circle.TopicId, members);
+    }
+
     public void RestorePresence(IReadOnlyList<PresenceSnapshot>? saved) => PresenceSystem.Restore(this, saved);
 
     public bool IsCampusEmpty() => PresenceSystem.IsEmpty(this);