fix(central-ui): resolve CentralUI-020..025 — auth-ping idle logout, DebugView race, push-handler disposal guard, JS-interop catch narrowing, claim-constant helper, SessionExpiry tests

tests/ScadaLink.CentralUI.Tests/Shared/DiffDialogTests.cs

@@ -13,9 +13,23 @@ namespace ScadaLink.CentralUI.Tests.Shared;
 /// </summary>
 public class DiffDialogTests : BunitContext
 {
+    /// <summary>
+    /// DiffDialog applies/removes a body scroll-lock class via JS interop on
+    /// open/close. CentralUI-023 narrowed those catch blocks so they no longer
+    /// swallow every exception — including bUnit's strict-mode unplanned-call
+    /// exception. Tests that exercise open/close must therefore register the
+    /// body-class calls so they do not surface as harness exceptions.
+    /// </summary>
+    private void SetupBodyLockInterop()
+    {
+        JSInterop.SetupVoid("document.body.classList.add", "modal-open");
+        JSInterop.SetupVoid("document.body.classList.remove", "modal-open");
+    }
+
     [Fact]
     public async Task DisposeAsync_WhileOpen_CompletesPendingTask()
     {
+        SetupBodyLockInterop();
         var cut = Render<DiffDialog>();
 
         // Open the dialog; the returned task represents the caller's await.
@@ -41,6 +55,7 @@ public class DiffDialogTests : BunitContext
     [Fact]
     public async Task Close_CompletesPendingTaskWithTrue()
     {
+        SetupBodyLockInterop();
         var cut = Render<DiffDialog>();
 
         // Block-bodied lambda so InvokeAsync sees a void delegate — it must NOT