Show the cluster's solar weather in a bandmap status bar

The reader follows N1MM's rules for WWV and WCY lines and the sh/wwv
table. The bar is hidden until the cluster has sent some.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/Nonemm.Spotting/ClusterClient.cs

@@ -29,6 +29,7 @@ public sealed class ClusterClient : IDisposable
     private readonly CancellationTokenSource stopping = new();
     private readonly LineAssembler lines = new();
     private readonly Queue<ClusterLine> recent = new();
+    private readonly SolarReader solar = new();
     private readonly Lock guard = new();
 
     private TcpClient? client;
@@ -80,6 +81,9 @@ public sealed class ClusterClient : IDisposable
 
     public event EventHandler<string>? LineArrived;
 
+    /// The node sent solar weather, as the text to show.
+    public event EventHandler<string>? SolarArrived;
+
     /// What went out to the node, so the telnet window can show the login and
     /// the commands beside the node's answers.
     public event EventHandler<string>? LineSent;
@@ -237,6 +241,10 @@ public sealed class ClusterClient : IDisposable
             Kind = kind;
             ConnectionChanged?.Invoke(this, IsConnected);
         }
+        if (solar.Read(line) is { } weather)
+        {
+            SolarArrived?.Invoke(this, weather);
+        }
         Spot? spot = SpotLine.Parse(line, DateTime.UtcNow);
         if (spot is not null)
         {