Add auto-close when notification becomes inactive

- Fleet alert forms now check every 30 seconds if notification is still active
- Automatically close if notification has ended or been deactivated
- Bump tray to 1.6.3, agent to 1.13.2

agent/ShopDbEndpointAgent.Tray/FleetAlertForm.cs

@@ -12,15 +12,20 @@ namespace ShopDbEndpointAgent.Tray;
 internal sealed class FleetAlertForm : Form
 {
     private readonly FleetAlert alert;
+    private readonly FleetAlertClient? client;
+    private readonly string? hostname;
     private System.Windows.Forms.Timer? countdownTimer;
+    private System.Windows.Forms.Timer? statusCheckTimer;
     private int remainingSeconds;
     private Label? countdownLabel;
 
     public event EventHandler? OnAcknowledgeClicked;
 
-    public FleetAlertForm(FleetAlert alert)
+    public FleetAlertForm(FleetAlert alert, FleetAlertClient? client = null, string? hostname = null)
     {
         this.alert = alert ?? throw new ArgumentNullException(nameof(alert));
+        this.client = client;
+        this.hostname = hostname;
 
         Text = string.Empty;
         FormBorderStyle = FormBorderStyle.None;
@@ -43,11 +48,46 @@ internal sealed class FleetAlertForm : Form
     private void FleetAlertForm_FormClosing(object? sender, FormClosingEventArgs e)
     {
         countdownTimer?.Stop();
+        statusCheckTimer?.Stop();
     }
 
     private void FleetAlertForm_Load(object? sender, EventArgs e)
     {
         System.Media.SystemSounds.Beep.Play();
+
+        if (client != null && hostname != null)
+        {
+            StartStatusCheck();
+        }
+    }
+
+    private void StartStatusCheck()
+    {
+        statusCheckTimer = new System.Windows.Forms.Timer { Interval = 30000 };
+        statusCheckTimer.Tick += StatusCheckTimer_Tick;
+        statusCheckTimer.Start();
+    }
+
+    private async void StatusCheckTimer_Tick(object? sender, EventArgs e)
+    {
+        if (client == null || hostname == null)
+            return;
+
+        try
+        {
+            var alerts = await client.FetchAlertsAsync(hostname, CancellationToken.None);
+            var stillActive = alerts?.Any(a => a.NotificationId == alert.NotificationId) ?? false;
+
+            if (!stillActive)
+            {
+                statusCheckTimer?.Stop();
+                Close();
+            }
+        }
+        catch
+        {
+            // Ignore errors - keep the form open if we can't check status
+        }
     }
 
     private void ApplyRoundedCorners()
@@ -280,6 +320,8 @@ internal sealed class FleetAlertForm : Form
         {
             countdownTimer?.Stop();
             countdownTimer?.Dispose();
+            statusCheckTimer?.Stop();
+            statusCheckTimer?.Dispose();
         }
         base.Dispose(disposing);
     }

agent/ShopDbEndpointAgent.Tray/FleetAlertWorker.cs

@@ -129,7 +129,7 @@ internal sealed class FleetAlertWorker : IDisposable
         {
             try
             {
-                using var form = new FleetAlertForm(alert);
+                using var form = new FleetAlertForm(alert, client, hostname);
                 form.OnAcknowledgeClicked += (s, e) => OnAlertAcknowledged(alert, token);
                 var result = form.ShowDialog();
             }

agent/ShopDbEndpointAgent.Tray/ShopDbEndpointAgent.Tray.csproj

@@ -76,7 +76,10 @@
 	<!-- 1.6.2: disable auto-dismiss timer. Fleet alerts now require manual
 	     acknowledgment only. Footer shows "Manual acknowledgment required" instead
 	     of countdown timer. -->
-	<Version>1.6.2</Version>
+	<!-- 1.6.3: auto-close when notification becomes inactive. Fleet alert forms now
+	     check every 30 seconds if the notification is still active on the server and
+	     automatically close if it has ended or been deactivated. -->
+	<Version>1.6.3</Version>
 	<InvariantGlobalization>true</InvariantGlobalization>
 	<RuntimeIdentifier>win-x64</RuntimeIdentifier>
 	<SelfContained>true</SelfContained>

agent/ShopDbEndpointAgent/ShopDbEndpointAgent.csproj

@@ -173,7 +173,9 @@
 		 is the side that listens, so an older tray simply never answers. -->
 	<!-- 1.13.1: coordinated release with tray 1.6.0 (fleet alert styling update).
 	     No agent code changes, but deployed together for version consistency. -->
-	<Version>1.13.1</Version>
+	<!-- 1.13.2: coordinated release with tray 1.6.3 (auto-close when inactive, crash fix).
+	     No agent code changes, but deployed together for version consistency. -->
+	<Version>1.13.2</Version>
 	<InvariantGlobalization>true</InvariantGlobalization>
 	<RuntimeIdentifier>win-x64</RuntimeIdentifier>
 	<SelfContained>true</SelfContained>