Show talk-circle partners and topic on the location panel and Now tab.

The frame and card share member ids; the client builds the sentence from the directory and locale.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/HSchool.Simulation.Tests/TalkCircleTests.cs

@@ -26,6 +26,13 @@ public class TalkCircleTests
             var rows = school.CapturePresence();
             Assert.Equal(TalkActions.Chat, rows.Single(row => row.PersonId == first.Id).ActionId);
             Assert.Equal(TalkActions.Chat, rows.Single(row => row.PersonId == second.Id).ActionId);
+            var circle = school.TalkCircleOf(first.Id);
+            Assert.NotNull(circle);
+            Assert.Contains(first.Id, circle.MemberIds);
+            Assert.Contains(second.Id, circle.MemberIds);
+            Assert.False(string.IsNullOrEmpty(circle.TopicId));
+            Assert.Equal(circle.MemberIds, school.TalkCircleOf(second.Id)?.MemberIds);
+            Assert.Null(school.TalkCircleOf("missing"));
         }
     }