feat(m9/T25): connection live-status indicators on the design page

src/ZB.MOM.WW.ScadaBridge.CentralUI/Components/Pages/Design/DataConnections.razor

@@ -1,10 +1,14 @@
 @page "/design/connections"
 @page "/design/data-connections"
 @using ZB.MOM.WW.ScadaBridge.Security
+@using ZB.MOM.WW.ScadaBridge.CentralUI.Services
 @using ZB.MOM.WW.ScadaBridge.Commons.Entities.Sites
 @using ZB.MOM.WW.ScadaBridge.Commons.Interfaces.Repositories
+@using ZB.MOM.WW.ScadaBridge.Commons.Types.Enums
 @attribute [Authorize(Policy = AuthorizationPolicies.RequireDesign)]
+@implements IDisposable
 @inject ISiteRepository SiteRepository
+@inject IConnectionHealthQueryService ConnectionHealthQuery
 @inject NavigationManager NavigationManager
 @inject IDialogService Dialog
 
@@ -80,6 +84,21 @@
                 {
                     <span class="tv-label" style="@labelStyle">@node.Label</span>
                     <span class="badge bg-info ms-2">@node.Connection!.Protocol</span>
+                    var health = _connectionHealth.TryGetValue(node.Connection!.Id, out var h)
+                        ? (ConnectionHealth?)h
+                        : null;
+                    @if (health is { } known)
+                    {
+                        <span class="badge @GetConnectionHealthBadge(known) ms-1"
+                              data-test="@($"conn-health-{node.Connection!.Id}")"
+                              aria-label="@($"Connection health: {known}")">@known</span>
+                    }
+                    else
+                    {
+                        <span class="badge bg-secondary ms-1"
+                              data-test="@($"conn-health-{node.Connection!.Id}")"
+                              aria-label="Connection health: unknown">Unknown</span>
+                    }
                 }
                 <span class="tv-meta">
                     <div class="dropdown dc-node-actions" @onclick:stopPropagation="true">
@@ -184,11 +203,48 @@
 
     private ToastNotification _toast = default!;
 
+    // M9-T25: live per-connection health, keyed by DataConnection.Id. Sourced from
+    // the existing site→central health transport via IConnectionHealthQueryService
+    // and refreshed on a ~10s poll, mirroring the Health dashboard's timer pattern.
+    // A connection absent from the map renders an "Unknown" badge (tolerates a site
+    // with no report yet — no crash).
+    private IReadOnlyDictionary<int, ConnectionHealth> _connectionHealth =
+        new Dictionary<int, ConnectionHealth>();
+    private Timer? _healthTimer;
+    private const int HealthRefreshSeconds = 10;
+
     private bool HasSiteSelected => ResolveSelectedSiteId() != null;
 
     protected override async Task OnInitializedAsync()
     {
         await LoadDataAsync();
+        await LoadConnectionHealthAsync();
+
+        // Poll the live health map on the same cadence as the Health dashboard.
+        // Best-effort: a failed query leaves the prior map in place rather than
+        // disturbing the tree.
+        _healthTimer = new Timer(_ =>
+        {
+            InvokeAsync(async () =>
+            {
+                await LoadConnectionHealthAsync();
+                StateHasChanged();
+            });
+        }, null, TimeSpan.FromSeconds(HealthRefreshSeconds), TimeSpan.FromSeconds(HealthRefreshSeconds));
+    }
+
+    // Best-effort load of the connection-id → health map. A transient fault leaves
+    // the existing badges untouched — health is advisory, never blocks the page.
+    private async Task LoadConnectionHealthAsync()
+    {
+        try
+        {
+            _connectionHealth = await ConnectionHealthQuery.GetConnectionHealthAsync();
+        }
+        catch
+        {
+            // Keep the prior map; the next poll retries.
+        }
     }
 
     private async Task LoadDataAsync()
@@ -310,4 +366,22 @@
             _toast.ShowError($"Delete failed: {ex.Message}");
         }
     }
+
+    // M9-T25: enum → Bootstrap badge class. Mirrors the Health dashboard's
+    // GetConnectionHealthBadge (Components/Pages/Monitoring/Health.razor) so the
+    // design page surfaces the same colour coding for the same status. Kept as a
+    // small local mirror — the Health helper is a private page-local method, not a
+    // shared component, so extracting it carries more risk than the duplication.
+    private static string GetConnectionHealthBadge(ConnectionHealth health) => health switch
+    {
+        ConnectionHealth.Connected => "bg-success",
+        ConnectionHealth.Connecting => "bg-warning text-dark",
+        ConnectionHealth.Disconnected => "bg-danger",
+        _ => "bg-secondary"
+    };
+
+    public void Dispose()
+    {
+        _healthTimer?.Dispose();
+    }
 }