Count from the log again on Reset Serial Numbers

The button started the numbers again at one. N1MM's manual says it "sets
serial numbers on all computers to the highest value in any of the logs,
plus 1", and its own handler re-reads the highest number per band out of
the log, so a mixed network came apart at exactly the point the button is
meant to repair: the N1MM stations counted on from the highest number and
this one started at one, sending numbers that had already gone out.

ContestSession.RestartNumbers fills the pool from the log, which is where
the reset now lands. SerialNumbersFrom is gone with it, and so is the pool
this station sent afterwards: N1MM sends none, because each station works
the same number out of its own copy of the log.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015NZkFxHde1iifAQemFTHxf

src/Nonemm.App/AppSession.cs

@@ -411,14 +411,15 @@ public sealed class AppSession : IDisposable
         }
     }
 
-    /// Starts the serial numbers again at one. The contacts already logged keep
-    /// the numbers they were sent with; it is the next number that changes.
+    /// Starts the serial numbers again from the log: the next number becomes
+    /// the highest one in it plus one. The contacts already logged keep the
+    /// numbers they were sent with. N1MM sends no pool with this — every
+    /// station works the same number out of its own copy of the log.
     public void ResetSerialNumbers()
     {
         if (Logging is not null)
         {
-            Logging.SerialNumbersFrom = DateTime.UtcNow;
-            _ = link?.SendSerialNumbersAsync(Logging.Numbers.Snapshot());
+            Logging.RestartNumbers();
             Changed?.Invoke(this, EventArgs.Empty);
         }
     }

src/Nonemm.App/Windows/NetworkStatusWindow.axaml.cs

@@ -378,7 +378,8 @@ public sealed partial class NetworkStatusWindow : RefreshableWindow
         }
     }
 
-    /// Starts the serial numbers again at one, here and at every station.
+    /// Counts the serial numbers from the log again, here and at every
+    /// station: the next number is the highest one logged plus one.
     private async void OnResetSerialNumbers(object? sender, RoutedEventArgs e)
     {
         if (link is null)
@@ -387,7 +388,7 @@ public sealed partial class NetworkStatusWindow : RefreshableWindow
         }
         session.ResetSerialNumbers();
         await link.SendResetSerialNumbersAsync();
-        Say("serial numbers start again at one");
+        Say($"serial numbers start again at {session.Logging?.NextNumberOn(null)}");
     }
 
     private void OnLogEverywhereChanged(object? sender, RoutedEventArgs e)