Merge branch 'worktree-agent-a9d87141c744e7733' into feat/instance-picker

tests/ZB.MOM.WW.ScadaBridge.CentralUI.Tests/Deployment/DebugViewInstancePickerTests.cs

@@ -1,3 +1,4 @@
+using System.Reflection;
 using System.Security.Claims;
 using Bunit;
 using Microsoft.AspNetCore.Components.Authorization;
@@ -21,7 +22,8 @@ namespace ZB.MOM.WW.ScadaBridge.CentralUI.Tests.Deployment;
 /// <c>&lt;select&gt;</c> to the shared <c>InstancePicker</c> area-tree combobox
 /// (design 2026-09-08). Pins that the page hands the picker the site's areas and
 /// its Enabled-only instance list, that drilling down the tree selects an instance,
-/// and that the selection still enables <em>Connect</em>.
+/// that the selection still enables <em>Connect</em>, and that a live connection
+/// locks the picker down.
 /// </summary>
 public class DebugViewInstancePickerTests : BunitContext
 {
@@ -153,4 +155,22 @@ public class DebugViewInstancePickerTests : BunitContext
             .First(b => b.TextContent.Contains("Connect"));
         Assert.False(connect.HasAttribute("disabled"));
     }
+
+    [Fact]
+    public void WhileConnected_ThePickerIsDisabled()
+    {
+        RegisterServices();
+        var cut = Render<DebugViewPage>();
+        cut.Find("[data-test='debug-site-select']").Change(SiteId.ToString());
+
+        // Mark the page connected the way the other DebugView page tests do —
+        // driving the real gRPC stream is not available to a bUnit render.
+        cut.InvokeAsync(() => typeof(DebugViewPage)
+            .GetField("_connected", BindingFlags.Instance | BindingFlags.NonPublic)!
+            .SetValue(cut.Instance, true));
+        cut.Render();
+
+        Assert.True(cut.Find("[data-test='debug-instance-input']").HasAttribute("disabled"));
+        Assert.True(cut.Find("[data-test='debug-instance-toggle']").HasAttribute("disabled"));
+    }
 }