test(e2e): assert destination renders, not just URL, in nav tests

tests/ZB.MOM.WW.ScadaBridge.CentralUI.PlaywrightTests/NavigationTests.cs

@@ -75,6 +75,27 @@ public class NavigationTests
         await ClickNavAndWait(page, linkText, expectedPath);
     }
 
+    // Maps each navigable route to the exact heading text rendered by that page.
+    private static readonly Dictionary<string, string> RouteHeadings = new()
+    {
+        ["/admin/sites"]                = "Site Management",
+        ["/admin/api-keys"]             = "API Key Management",
+        ["/admin/ldap-mappings"]        = "LDAP Group Mappings",
+        ["/notifications/smtp"]         = "SMTP Configuration",
+        ["/notifications/lists"]        = "Notification Lists",
+        ["/notifications/report"]       = "Notification Report",
+        ["/notifications/kpis"]         = "Notification KPIs",
+        ["/design/templates"]           = "Templates",
+        ["/design/shared-scripts"]      = "Shared Scripts",
+        ["/design/connections"]         = "Connections",
+        ["/design/external-systems"]    = "Integration Definitions",
+        ["/deployment/topology"]        = "Topology",
+        ["/deployment/deployments"]     = "Deployment Status",
+        ["/monitoring/health"]          = "Health Dashboard",
+        ["/monitoring/event-logs"]      = "Site Event Logs",
+        ["/monitoring/parked-messages"] = "Parked Messages",
+    };
+
     private static async Task ClickNavAndWait(IPage page, string linkText, string expectedPath)
     {
         // Sections are collapsed by default — open them so the link is in the DOM.
@@ -82,6 +103,13 @@ public class NavigationTests
         await page.Locator($"nav a:has-text('{linkText}')").ClickAsync();
         await PlaywrightFixture.WaitForPathAsync(page, expectedPath);
         Assert.Contains(expectedPath, page.Url);
+
+        // Verify the destination page actually rendered its heading (catches 500s
+        // and blank renders that a URL-only check would miss).
+        var expectedHeading = RouteHeadings[expectedPath];
+        await Assertions.Expect(
+            page.Locator("h1, h4, h5", new() { HasText = expectedHeading })
+        ).ToBeVisibleAsync();
     }
 
     private static ILocatorAssertions Expect(ILocator locator) =>